themes and some refractoring

Reviewed-on: #6

lib/main.dart

@@ -1,4 +1,6 @@
 import 'package:flutter/material.dart';
+import 'package:hirameki_srs/src/models/theme_model.dart';
+import 'package:hirameki_srs/src/services/vocab_deck_repository.dart';
 import 'package:provider/provider.dart';
 import 'package:flutter_dotenv/flutter_dotenv.dart';
 import 'src/services/deck_repository.dart';
@@ -8,14 +10,16 @@ void main() async {
   WidgetsFlutterBinding.ensureInitialized();
   try {
     await dotenv.load(fileName: ".env");
-  } catch (e) {
-    // It's okay if the .env file is not found.
-    // This is expected in release builds.
-  }
+    // No need to catch because the file is only needed for dev
+  } catch (_) {}
 
   runApp(
-    Provider<DeckRepository>(
-      create: (_) => DeckRepository(),
+    MultiProvider(
+      providers: [
+        Provider<DeckRepository>(create: (_) => DeckRepository()),
+        Provider<VocabDeckRepository>(create: (_) => VocabDeckRepository()),
+        ChangeNotifierProvider<ThemeModel>(create: (_) => ThemeModel()),
+      ],
       child: const WkApp(),
     ),
   );
@@ -26,11 +30,15 @@ class WkApp extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return MaterialApp(
-      title: 'Hirameki SRS',
-      debugShowCheckedModeBanner: false,
-      theme: ThemeData.dark(useMaterial3: true),
-      home: const StartScreen(),
+    return Consumer<ThemeModel>(
+      builder: (context, themeModel, child) {
+        return MaterialApp(
+          title: 'Hirameki SRS',
+          debugShowCheckedModeBanner: false,
+          theme: themeModel.currentTheme,
+          home: const StartScreen(),
+        );
+      },
     );
   }
-}
+}

lib/src/api/wk_client.dart

@@ -1,14 +1,24 @@
 import 'dart:convert';
 import 'package:http/http.dart' as http;
+import '../models/subject.dart';
+import '../models/kanji_item.dart';
+import '../models/vocabulary_item.dart';
 
 class WkClient {
   final String apiKey;
   final Map<String, String> headers;
   final String base = 'https://api.wanikani.com/v2';
 
-  WkClient(this.apiKey) : headers = {'Authorization': 'Bearer $apiKey', 'Wanikani-Revision': '20170710', 'Accept': 'application/json'};
+  WkClient(this.apiKey)
+    : headers = {
+        'Authorization': 'Bearer $apiKey',
+        'Wanikani-Revision': '20170710',
+        'Accept': 'application/json',
+      };
 
-  Future<List<Map<String, dynamic>>> fetchAllAssignments({List<String>? subjectTypes}) async {
+  Future<List<Map<String, dynamic>>> fetchAllAssignments({
+    List<String>? subjectTypes,
+  }) async {
     final out = <Map<String, dynamic>>[];
     String url = '$base/assignments?page=1';
     if (subjectTypes != null && subjectTypes.isNotEmpty) {
@@ -30,13 +40,15 @@ class WkClient {
     return out;
   }
 
-  Future<List<Map<String, dynamic>>> fetchAllSubjects({List<String>? types}) async {
+  Future<List<Map<String, dynamic>>> fetchAllSubjects({
+    List<String>? types,
+  }) async {
     final out = <Map<String, dynamic>>[];
     String url = '$base/subjects';
     if (types != null && types.isNotEmpty) {
       url += '?types=${types.join(',')}';
     }
-    
+
     while (url.isNotEmpty) {
       final resp = await http.get(Uri.parse(url), headers: headers);
       if (resp.statusCode != 200) throw Exception('API ${resp.statusCode}');
@@ -56,7 +68,10 @@ class WkClient {
     final out = <Map<String, dynamic>>[];
     const batch = 100;
     for (var i = 0; i < ids.length; i += batch) {
-      final chunk = ids.sublist(i, i + batch > ids.length ? ids.length : i + batch);
+      final chunk = ids.sublist(
+        i,
+        i + batch > ids.length ? ids.length : i + batch,
+      );
       String url = '$base/subjects?ids=${chunk.join(',')}&page=1';
       while (true) {
         final resp = await http.get(Uri.parse(url), headers: headers);
@@ -73,4 +88,13 @@ class WkClient {
     }
     return out;
   }
+  static Subject createSubjectFromMap(Map<String, dynamic> map) {
+    final String object = map['object'];
+    if (object == 'kanji') {
+      return KanjiItem.fromSubject(map);
+    } else if (object == 'vocabulary') {
+      return VocabularyItem.fromSubject(map);
+    }
+    throw Exception('Unknown subject type: $object');
+  }
 }

lib/src/models/custom_kanji_item.dart

@@ -1,31 +1,48 @@
-
 class CustomKanjiItem {
   final String characters;
   final String meaning;
   final String? kanji;
   final bool useInterval;
-  int srsLevel;
-  DateTime? nextReview;
+  SrsData srsData;
 
   CustomKanjiItem({
     required this.characters,
     required this.meaning,
     this.kanji,
     this.useInterval = false,
-    this.srsLevel = 0,
-    this.nextReview,
-  });
+    SrsData? srsData,
+  }) : srsData = srsData ?? SrsData();
 
   factory CustomKanjiItem.fromJson(Map<String, dynamic> json) {
+    SrsData srsData;
+    if (json['srsData'] != null) {
+      srsData = SrsData.fromJson(json['srsData']);
+      if (json['nextReview'] != null) {
+        final oldNextReview = DateTime.parse(json['nextReview'] as String);
+        srsData.japaneseToEnglishNextReview ??= oldNextReview;
+        srsData.englishToJapaneseNextReview ??= oldNextReview;
+        srsData.listeningComprehensionNextReview ??= oldNextReview;
+      }
+    } else {
+      DateTime? nextReview = json['nextReview'] != null
+          ? DateTime.parse(json['nextReview'] as String)
+          : null;
+      srsData = SrsData(
+        japaneseToEnglish: json['srsLevel'] as int? ?? 0,
+        japaneseToEnglishNextReview: nextReview,
+        englishToJapanese: json['srsLevel'] as int? ?? 0,
+        englishToJapaneseNextReview: nextReview,
+        listeningComprehension: json['srsLevel'] as int? ?? 0,
+        listeningComprehensionNextReview: nextReview,
+      );
+    }
+
     return CustomKanjiItem(
       characters: json['characters'] as String,
       meaning: json['meaning'] as String,
       kanji: json['kanji'] as String?,
       useInterval: json['useInterval'] as bool? ?? false,
-      srsLevel: json['srsLevel'] as int? ?? 0,
-      nextReview: json['nextReview'] != null
-          ? DateTime.parse(json['nextReview'] as String)
-          : null,
+      srsData: srsData,
     );
   }
 
@@ -35,8 +52,57 @@ class CustomKanjiItem {
       'meaning': meaning,
       'kanji': kanji,
       'useInterval': useInterval,
-      'srsLevel': srsLevel,
-      'nextReview': nextReview?.toIso8601String(),
+      'srsData': srsData.toJson(),
+    };
+  }
+}
+
+class SrsData {
+  int japaneseToEnglish;
+  DateTime? japaneseToEnglishNextReview;
+  int englishToJapanese;
+  DateTime? englishToJapaneseNextReview;
+  int listeningComprehension;
+  DateTime? listeningComprehensionNextReview;
+
+  SrsData({
+    this.japaneseToEnglish = 0,
+    this.japaneseToEnglishNextReview,
+    this.englishToJapanese = 0,
+    this.englishToJapaneseNextReview,
+    this.listeningComprehension = 0,
+    this.listeningComprehensionNextReview,
+  });
+
+  factory SrsData.fromJson(Map<String, dynamic> json) {
+    return SrsData(
+      japaneseToEnglish: json['japaneseToEnglish'] as int? ?? 0,
+      japaneseToEnglishNextReview: json['japaneseToEnglishNextReview'] != null
+          ? DateTime.parse(json['japaneseToEnglishNextReview'] as String)
+          : null,
+      englishToJapanese: json['englishToJapanese'] as int? ?? 0,
+      englishToJapaneseNextReview: json['englishToJapaneseNextReview'] != null
+          ? DateTime.parse(json['englishToJapaneseNextReview'] as String)
+          : null,
+      listeningComprehension: json['listeningComprehension'] as int? ?? 0,
+      listeningComprehensionNextReview:
+          json['listeningComprehensionNextReview'] != null
+          ? DateTime.parse(json['listeningComprehensionNextReview'] as String)
+          : null,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'japaneseToEnglish': japaneseToEnglish,
+      'japaneseToEnglishNextReview': japaneseToEnglishNextReview
+          ?.toIso8601String(),
+      'englishToJapanese': englishToJapanese,
+      'englishToJapaneseNextReview': englishToJapaneseNextReview
+          ?.toIso8601String(),
+      'listeningComprehension': listeningComprehension,
+      'listeningComprehensionNextReview': listeningComprehensionNextReview
+          ?.toIso8601String(),
     };
   }
 }

lib/src/models/kanji_item.dart

@@ -1,54 +1,24 @@
-enum QuizMode { kanjiToEnglish, englishToKanji, reading }
+import 'subject.dart';
 
-class SrsItem {
-  final int kanjiId;
-  final QuizMode quizMode;
-  final String? readingType; // 'onyomi' or 'kunyomi'
-  int srsStage;
-  DateTime lastAsked;
-
-  SrsItem({
-    required this.kanjiId,
-    required this.quizMode,
-    this.readingType,
-    this.srsStage = 0,
-    DateTime? lastAsked,
-  }) : lastAsked = lastAsked ?? DateTime.now();
-}
-
-class KanjiItem {
-  final int id;
-  final int level;
-  final String characters;
-  final List<String> meanings;
+class KanjiItem extends Subject {
   final List<String> onyomi;
   final List<String> kunyomi;
-  final Map<String, SrsItem> srsItems = {};
 
   KanjiItem({
-    required this.id,
-    required this.level,
-    required this.characters,
-    required this.meanings,
+    required super.id,
+    required super.level,
+    required super.characters,
+    required super.meanings,
     required this.onyomi,
     required this.kunyomi,
   });
 
   factory KanjiItem.fromSubject(Map<String, dynamic> subj) {
-    final int id = subj['id'] as int;
-    final data = subj['data'] as Map<String, dynamic>;
-    final int level = data['level'] as int;
-    final String characters = (data['characters'] ?? '') as String;
-    final List<String> meanings = <String>[];
+    final commonFields = Subject.parseCommonFields(subj);
+    final data = commonFields['data'] as Map<String, dynamic>;
     final List<String> onyomi = <String>[];
     final List<String> kunyomi = <String>[];
 
-    if (data['meanings'] != null) {
-      for (final m in data['meanings'] as List) {
-        meanings.add((m['meaning'] as String).toLowerCase());
-      }
-    }
-
     if (data['readings'] != null) {
       for (final r in data['readings'] as List) {
         final typ = r['type'] as String? ?? '';
@@ -62,10 +32,10 @@ class KanjiItem {
     }
 
     return KanjiItem(
-      id: id,
-      level: level,
-      characters: characters,
-      meanings: meanings,
+      id: commonFields['id'] as int,
+      level: commonFields['level'] as int,
+      characters: commonFields['characters'] as String,
+      meanings: commonFields['meanings'] as List<String>,
       onyomi: onyomi,
       kunyomi: kunyomi,
     );
@@ -83,89 +53,3 @@ String _katakanaToHiragana(String input) {
   }
   return buf.toString();
 }
-
-enum VocabQuizMode { vocabToEnglish, englishToVocab, audioToEnglish }
-
-class VocabSrsItem {
-  final int vocabId;
-  final VocabQuizMode quizMode;
-  int srsStage;
-  DateTime lastAsked;
-
-  VocabSrsItem({
-    required this.vocabId,
-    required this.quizMode,
-    this.srsStage = 0,
-    DateTime? lastAsked,
-  }) : lastAsked = lastAsked ?? DateTime.now();
-}
-
-class PronunciationAudio {
-  final String url;
-  final String gender;
-
-  PronunciationAudio({required this.url, required this.gender});
-}
-
-class VocabularyItem {
-  final int id;
-  final int level;
-  final String characters;
-  final List<String> meanings;
-  final List<String> readings;
-  final List<PronunciationAudio> pronunciationAudios;
-  final Map<String, VocabSrsItem> srsItems = {};
-
-  VocabularyItem(
-      {required this.id,
-      required this.level,
-      required this.characters,
-      required this.meanings,
-      required this.readings,
-      required this.pronunciationAudios});
-
-  factory VocabularyItem.fromSubject(Map<String, dynamic> subj) {
-    final int id = subj['id'] as int;
-    final data = subj['data'] as Map<String, dynamic>;
-    final int level = data['level'] as int;
-    final String characters = (data['characters'] ?? '') as String;
-    final List<String> meanings = <String>[];
-    final List<String> readings = <String>[];
-    final List<PronunciationAudio> pronunciationAudios = <PronunciationAudio>[];
-
-    if (data['meanings'] != null) {
-      for (final m in data['meanings'] as List) {
-        meanings.add((m['meaning'] as String).toLowerCase());
-      }
-    }
-
-    if (data['readings'] != null) {
-      for (final r in data['readings'] as List) {
-        readings.add(r['reading'] as String);
-      }
-    }
-
-    if (data['pronunciation_audios'] != null) {
-      for (final audio in data['pronunciation_audios'] as List) {
-        final url = audio['url'] as String?;
-        final metadata = audio['metadata'] as Map<String, dynamic>?;
-        final gender = metadata?['gender'] as String?;
-
-        if (url != null && gender != null) {
-          pronunciationAudios.add(PronunciationAudio(
-            url: url,
-            gender: gender,
-          ));
-        }
-      }
-    }
-
-    return VocabularyItem(
-        id: id,
-        level: level,
-        characters: characters,
-        meanings: meanings,
-        readings: readings,
-        pronunciationAudios: pronunciationAudios);
-  }
-}

lib/src/models/srs_item.dart

@@ -0,0 +1,17 @@
+enum QuizMode { kanjiToEnglish, englishToKanji, reading, vocabToEnglish, englishToVocab, audioToEnglish }
+
+class SrsItem {
+  final int subjectId;
+  final QuizMode quizMode;
+  final String? readingType;
+  int srsStage;
+  DateTime lastAsked;
+
+  SrsItem({
+    required this.subjectId,
+    required this.quizMode,
+    this.readingType,
+    this.srsStage = 0,
+    DateTime? lastAsked,
+  }) : lastAsked = lastAsked ?? DateTime.now();
+}

lib/src/models/subject.dart

@@ -0,0 +1,38 @@
+import 'srs_item.dart';
+
+abstract class Subject {
+  final int id;
+  final int level;
+  final String characters;
+  final List<String> meanings;
+  final Map<String, SrsItem> srsItems = {};
+
+  Subject({
+    required this.id,
+    required this.level,
+    required this.characters,
+    required this.meanings,
+  });
+
+  static Map<String, dynamic> parseCommonFields(Map<String, dynamic> subj) {
+    final int id = subj['id'] as int;
+    final data = subj['data'] as Map<String, dynamic>;
+    final int level = data['level'] as int;
+    final String characters = (data['characters'] ?? '') as String;
+    final List<String> meanings = <String>[];
+
+    if (data['meanings'] != null) {
+      for (final m in data['meanings'] as List) {
+        meanings.add((m['meaning'] as String).toLowerCase());
+      }
+    }
+
+    return {
+      'id': id,
+      'level': level,
+      'characters': characters,
+      'meanings': meanings,
+      'data': data,
+    };
+  }
+}

lib/src/models/subject_factory.dart

@@ -0,0 +1,15 @@
+import 'kanji_item.dart';
+import 'vocabulary_item.dart';
+import 'subject.dart';
+
+class SubjectFactory {
+  static Subject fromMap(Map<String, dynamic> map) {
+    final String object = map['object'];
+    if (object == 'kanji') {
+      return KanjiItem.fromSubject(map);
+    } else if (object == 'vocabulary') {
+      return VocabularyItem.fromSubject(map);
+    }
+    throw Exception('Unknown subject type: $object');
+  }
+}

lib/src/models/theme_model.dart

@@ -0,0 +1,13 @@
+import 'package:flutter/material.dart';
+import 'package:hirameki_srs/src/themes.dart';
+
+class ThemeModel extends ChangeNotifier {
+  ThemeData _currentTheme = Themes.dark;
+
+  ThemeData get currentTheme => _currentTheme;
+
+  void setTheme(ThemeData theme) {
+    _currentTheme = theme;
+    notifyListeners();
+  }
+}

lib/src/models/vocabulary_item.dart

@@ -0,0 +1,56 @@
+import 'subject.dart';
+
+class PronunciationAudio {
+  final String url;
+  final String gender;
+
+  PronunciationAudio({required this.url, required this.gender});
+}
+
+class VocabularyItem extends Subject {
+  final List<String> readings;
+  final List<PronunciationAudio> pronunciationAudios;
+
+  VocabularyItem({
+    required super.id,
+    required super.level,
+    required super.characters,
+    required super.meanings,
+    required this.readings,
+    required this.pronunciationAudios,
+  });
+
+  factory VocabularyItem.fromSubject(Map<String, dynamic> subj) {
+    final commonFields = Subject.parseCommonFields(subj);
+    final data = commonFields['data'] as Map<String, dynamic>;
+    final List<String> readings = <String>[];
+    final List<PronunciationAudio> pronunciationAudios = <PronunciationAudio>[];
+
+    if (data['readings'] != null) {
+      for (final r in data['readings'] as List) {
+        readings.add(r['reading'] as String);
+      }
+    }
+
+    if (data['pronunciation_audios'] != null) {
+      for (final audio in data['pronunciation_audios'] as List) {
+        final url = audio['url'] as String?;
+        final metadata = audio['metadata'] as Map<String, dynamic>?;
+        final gender = metadata?['gender'] as String?;
+
+        if (url != null && gender != null) {
+          pronunciationAudios.add(PronunciationAudio(url: url, gender: gender));
+        }
+      }
+    }
+
+    return VocabularyItem(
+      id: commonFields['id'] as int,
+      level: commonFields['level'] as int,
+      characters: commonFields['characters'] as String,
+      meanings: commonFields['meanings'] as List<String>,
+      readings: readings,
+      pronunciationAudios: pronunciationAudios,
+    );
+  }
+}

lib/src/screens/add_card_screen.dart

@@ -1,4 +1,3 @@
-
 import 'package:flutter/material.dart';
 import 'package:kana_kit/kana_kit.dart';
 import '../models/custom_kanji_item.dart';
@@ -50,12 +49,22 @@ class _AddCardScreenState extends State<AddCardScreen> {
 
   void _saveCard() {
     if (_formKey.currentState!.validate()) {
+      final srsData = _useInterval
+          ? SrsData(
+              japaneseToEnglishNextReview: DateTime.now(),
+              englishToJapaneseNextReview: DateTime.now(),
+              listeningComprehensionNextReview: DateTime.now(),
+            )
+          : SrsData();
+
       final newItem = CustomKanjiItem(
         characters: _japaneseController.text,
         meaning: _englishController.text,
-        kanji: _kanjiController.text.isNotEmpty ? _kanjiController.text : null,
+        kanji: _kanjiController.text.trim().isNotEmpty
+            ? _kanjiController.text.trim()
+            : null,
         useInterval: _useInterval,
-        nextReview: _useInterval ? DateTime.now() : null,
+        srsData: srsData,
       );
       _deckRepository.addCard(newItem);
       Navigator.of(context).pop();
@@ -65,9 +74,7 @@ class _AddCardScreenState extends State<AddCardScreen> {
   @override
   Widget build(BuildContext context) {
     return Scaffold(
-      appBar: AppBar(
-        title: const Text('Add New Card'),
-      ),
+      appBar: AppBar(title: const Text('Add New Card')),
       body: Padding(
         padding: const EdgeInsets.all(16.0),
         child: Form(

lib/src/screens/browse_screen.dart

@@ -1,11 +1,18 @@
+import 'dart:convert';
 import 'package:flutter/material.dart';
+import 'package:hirameki_srs/src/themes.dart';
 import 'package:provider/provider.dart';
+import 'package:http/http.dart' as http;
 import '../models/kanji_item.dart';
+import '../models/vocabulary_item.dart';
+import '../models/srs_item.dart';
 import '../services/deck_repository.dart';
+import 'package:hirameki_srs/src/services/vocab_deck_repository.dart';
 import '../services/custom_deck_repository.dart';
 import '../models/custom_kanji_item.dart';
 import 'settings_screen.dart';
 import 'custom_card_details_screen.dart';
+import 'add_card_screen.dart';
 
 class BrowseScreen extends StatefulWidget {
   const BrowseScreen({super.key});
@@ -14,7 +21,8 @@ class BrowseScreen extends StatefulWidget {
   State<BrowseScreen> createState() => _BrowseScreenState();
 }
 
-class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderStateMixin {
+class _BrowseScreenState extends State<BrowseScreen>
+    with SingleTickerProviderStateMixin {
   late TabController _tabController;
   late PageController _kanjiPageController;
   late PageController _vocabPageController;
@@ -46,7 +54,7 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
     _vocabPageController = PageController();
 
     _tabController.addListener(() {
-      setState(() {}); // Rebuild to update the level selector
+      setState(() {});
     });
 
     _kanjiPageController.addListener(() {
@@ -90,13 +98,17 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
-            const Text('WaniKani API key is not set.', style: TextStyle(color: Colors.white)),
+            Text(
+              'WaniKani API key is not set.',
+              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+            ),
             const SizedBox(height: 16),
             ElevatedButton(
               onPressed: () async {
                 await Navigator.of(context).push(
                   MaterialPageRoute(builder: (_) => const SettingsScreen()),
                 );
+                if (!mounted) return;
                 _loadDecks();
               },
               child: const Text('Go to Settings'),
@@ -111,9 +123,9 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
-            const CircularProgressIndicator(color: Colors.blueAccent),
+            CircularProgressIndicator(color: Theme.of(context).colorScheme.primary),
             const SizedBox(height: 16),
-            Text(_status, style: const TextStyle(color: Colors.white)),
+            Text(_status, style: TextStyle(color: Theme.of(context).colorScheme.onSurface)),
           ],
         ),
       );
@@ -124,22 +136,28 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
 
   Widget _buildCustomSrsTab() {
     if (_customDeck.isEmpty) {
-      return const Center(
-        child: Text('No custom cards yet.', style: TextStyle(color: Colors.white)),
+      return Center(
+        child: Text(
+          'No custom cards yet.',
+          style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+        ),
       );
     }
     return _buildCustomGridView(_customDeck);
   }
 
   Widget _buildPaginatedView(
-      Map<int, List<dynamic>> groupedItems,
-      List<int> sortedLevels,
-      PageController pageController,
-      Widget Function(List<dynamic>) buildPageContent) {
+    Map<int, List<dynamic>> groupedItems,
+    List<int> sortedLevels,
+    PageController pageController,
+    Widget Function(List<dynamic>) buildPageContent,
+  ) {
     if (sortedLevels.isEmpty) {
-      return const Center(
-        child:
-            Text('No items to display.', style: TextStyle(color: Colors.white)),
+      return Center(
+        child: Text(
+          'No items to display.',
+          style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+        ),
       );
     }
 
@@ -156,10 +174,11 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
               padding: const EdgeInsets.all(16.0),
               child: Text(
                 'Level $level',
-                style: const TextStyle(
-                    fontSize: 24,
-                    color: Colors.white,
-                    fontWeight: FontWeight.bold),
+                style: TextStyle(
+                  fontSize: 24,
+                  color: Theme.of(context).colorScheme.onSurface,
+                  fontWeight: FontWeight.bold,
+                ),
               ),
             ),
             Expanded(child: buildPageContent(levelItems)),
@@ -179,7 +198,7 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
 
     return Container(
       padding: const EdgeInsets.symmetric(vertical: 8.0),
-      color: const Color(0xFF1F1F1F),
+      color: Theme.of(context).colorScheme.surfaceContainer,
       height: 60,
       child: SingleChildScrollView(
         scrollDirection: Axis.horizontal,
@@ -192,11 +211,17 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
               padding: const EdgeInsets.symmetric(horizontal: 4.0),
               child: ElevatedButton(
                 onPressed: () {
-                  controller.animateToPage(index, duration: const Duration(milliseconds: 300), curve: Curves.easeInOut);
+                  controller.animateToPage(
+                    index,
+                    duration: const Duration(milliseconds: 300),
+                    curve: Curves.easeInOut,
+                  );
                 },
                 style: ElevatedButton.styleFrom(
-                  backgroundColor: isSelected ? Colors.blueAccent : const Color(0xFF333333),
-                  foregroundColor: Colors.white,
+                  backgroundColor: isSelected
+                      ? Theme.of(context).colorScheme.primary
+                      : Theme.of(context).colorScheme.surfaceContainerHighest,
+                  foregroundColor: Theme.of(context).colorScheme.onPrimary,
                   shape: const CircleBorder(),
                   padding: const EdgeInsets.all(12),
                 ),
@@ -222,8 +247,7 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
         final item = items[index];
         return GestureDetector(
           onTap: () => _showReadingsDialog(item),
-          child:
-              _buildSrsItemCard(item.characters, item.srsItems.values.toList()),
+          child: _buildSrsItemCard(item),
         );
       },
       padding: const EdgeInsets.all(8),
@@ -241,68 +265,102 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
   }
 
   Widget _buildVocabListTile(VocabularyItem item) {
-    final avgSrsStage = item.srsItems.isNotEmpty
-        ? item.srsItems.values
-                .map((s) => s.srsStage)
-                .reduce((a, b) => a + b) /
-            item.srsItems.length
-        : 0.0;
+    final requiredModes = <String>[
+      QuizMode.vocabToEnglish.toString(),
+      QuizMode.englishToVocab.toString(),
+      QuizMode.audioToEnglish.toString(),
+    ];
 
-    return Card(
-      color: const Color(0xFF1E1E1E),
-      margin: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
-      child: Padding(
-        padding: const EdgeInsets.all(12.0),
-        child: Row(
-          children: [
-            Expanded(
-              child: Text(
-                item.characters,
-                style: const TextStyle(fontSize: 24, color: Colors.white),
+    int minSrsStage = 9;
+
+    for (final mode in requiredModes) {
+      final srsItem = item.srsItems[mode];
+      if (srsItem == null) {
+        minSrsStage = 0;
+        break;
+      }
+      if (srsItem.srsStage < minSrsStage) {
+        minSrsStage = srsItem.srsStage;
+      }
+    }
+
+    return GestureDetector(
+      onTap: () => _showVocabDetailsDialog(context, item),
+      child: Card(
+        color: Theme.of(context).colorScheme.surfaceContainer,
+        margin: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
+        child: Padding(
+          padding: const EdgeInsets.all(12.0),
+          child: Row(
+            children: [
+              Expanded(
+                child: Text(
+                  item.characters,
+                  style: TextStyle(fontSize: 24, color: Theme.of(context).colorScheme.onSurface),
+                ),
               ),
-            ),
-            const SizedBox(width: 16),
-            Expanded(
-              flex: 2,
-              child: Column(
-                crossAxisAlignment: CrossAxisAlignment.start,
-                children: [
-                  Text(
-                    item.meanings.join(', '),
-                    style: const TextStyle(color: Colors.grey),
-                    overflow: TextOverflow.ellipsis,
-                  ),
-                  const SizedBox(height: 8),
-                  _buildSrsIndicator(avgSrsStage.round()),
-                ],
+              const SizedBox(width: 16),
+              Expanded(
+                flex: 2,
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    Text(
+                      item.meanings.join(', '),
+                      style: TextStyle(color: Theme.of(context).colorScheme.onSurfaceVariant),
+                      overflow: TextOverflow.ellipsis,
+                    ),
+                    const SizedBox(height: 8),
+                    _buildSrsIndicator(minSrsStage),
+                  ],
+                ),
               ),
-            ),
-          ],
+            ],
+          ),
         ),
       ),
     );
   }
 
-  Widget _buildSrsItemCard(String characters, List<dynamic> srsItems) {
-    final avgSrsStage = srsItems.isNotEmpty
-        ? srsItems.map((s) => s.srsStage).reduce((a, b) => a + b) /
-            srsItems.length
-        : 0.0;
+  Widget _buildSrsItemCard(KanjiItem item) {
+    final requiredModes = <String>[
+      QuizMode.kanjiToEnglish.toString(),
+      QuizMode.englishToKanji.toString(),
+    ];
+    if (item.onyomi.isNotEmpty) {
+      requiredModes.add('${QuizMode.reading}onyomi');
+    }
+    if (item.kunyomi.isNotEmpty) {
+      requiredModes.add('${QuizMode.reading}kunyomi');
+    }
+
+    int minSrsStage = 9;
+
+    for (final mode in requiredModes) {
+      final srsItem = item.srsItems[mode];
+      if (srsItem == null) {
+        minSrsStage = 0;
+        break;
+      }
+      if (srsItem.srsStage < minSrsStage) {
+        minSrsStage = srsItem.srsStage;
+      }
+    }
 
     return Card(
-      color: const Color(0xFF1E1E1E),
+      color: Theme.of(context).colorScheme.surfaceContainer,
       child: Padding(
         padding: const EdgeInsets.all(8.0),
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
             Text(
-              characters,
-              style: const TextStyle(fontSize: 32, color: Colors.white),
+              item.characters,
+              style: TextStyle(fontSize: 32, color: Theme.of(context).colorScheme.onSurface),
               textAlign: TextAlign.center,
             ),
             const SizedBox(height: 8),
-            _buildSrsIndicator(avgSrsStage.round()),
+            _buildSrsIndicator(minSrsStage),
           ],
         ),
       ),
@@ -317,8 +375,8 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
         child: SizedBox(
           height: 10,
           child: LinearProgressIndicator(
-            value: level / 9.0, // Max SRS level is 9
-            backgroundColor: Colors.grey[800],
+            value: level / 9.0,
+            backgroundColor: Theme.of(context).colorScheme.surfaceContainerHighest,
             valueColor: AlwaysStoppedAnimation<Color>(
               _getColorForSrsLevel(level),
             ),
@@ -329,62 +387,114 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
   }
 
   Color _getColorForSrsLevel(int level) {
-    if (level >= 9) return Colors.purple;
-    if (level >= 8) return Colors.blue;
-    if (level >= 7) return Colors.lightBlue;
-    if (level >= 5) return Colors.green;
-    if (level >= 3) return Colors.yellow;
-    if (level >= 1) return Colors.orange;
-    return Colors.red;
+    final srsColors = Theme.of(context).srsColors;
+    if (level >= 9) return srsColors.level9;
+    if (level >= 8) return srsColors.level8;
+    if (level >= 7) return srsColors.level7;
+    if (level >= 6) return srsColors.level6;
+    if (level >= 5) return srsColors.level5;
+    if (level >= 4) return srsColors.level4;
+    if (level >= 3) return srsColors.level3;
+    if (level >= 2) return srsColors.level2;
+    if (level >= 1) return srsColors.level1;
+    return Colors.grey;
   }
 
   void _showReadingsDialog(KanjiItem kanji) {
+    final srsScores = <String, int>{
+      'JP -> EN': 0,
+      'EN -> JP': 0,
+      'Reading (onyomi)': 0,
+      'Reading (kunyomi)': 0,
+    };
+
+    for (final entry in kanji.srsItems.entries) {
+      final srsItem = entry.value;
+      switch (srsItem.quizMode) {
+        case QuizMode.kanjiToEnglish:
+          srsScores['JP -> EN'] = srsItem.srsStage;
+          break;
+        case QuizMode.englishToKanji:
+          srsScores['EN -> JP'] = srsItem.srsStage;
+          break;
+        case QuizMode.reading:
+          if (srsItem.readingType == 'onyomi') {
+            srsScores['Reading (onyomi)'] = srsItem.srsStage;
+          } else if (srsItem.readingType == 'kunyomi') {
+            srsScores['Reading (kunyomi)'] = srsItem.srsStage;
+          }
+          break;
+        default:
+          break;
+      }
+    }
+
     showDialog(
       context: context,
-      builder: (context) {
+      builder: (dialogContext) {
         return AlertDialog(
-          backgroundColor: const Color(0xFF1E1E1E),
+          backgroundColor: Theme.of(context).colorScheme.surfaceContainer,
           title: Text(
             'Details for ${kanji.characters}',
-            style: const TextStyle(color: Colors.white),
+            style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
           ),
-          content: Column(
-            mainAxisSize: MainAxisSize.min,
-            crossAxisAlignment: CrossAxisAlignment.start,
-            children: [
-              Text(
-                'Level: ${kanji.level}',
-                style: const TextStyle(color: Colors.white),
-              ),
-              const SizedBox(height: 16),
-              if (kanji.meanings.isNotEmpty)
+          content: SingleChildScrollView(
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
                 Text(
-                  'Meanings: ${kanji.meanings.join(', ')}',
-                  style: const TextStyle(color: Colors.white),
+                  'Level: ${kanji.level}',
+                  style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
                 ),
-              const SizedBox(height: 16),
-              if (kanji.onyomi.isNotEmpty)
+                const SizedBox(height: 16),
+                if (kanji.meanings.isNotEmpty)
+                  Text(
+                    'Meanings: ${kanji.meanings.join(', ')}',
+                    style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+                  ),
+                const SizedBox(height: 16),
+                if (kanji.onyomi.isNotEmpty)
+                  Text(
+                    'On\'yomi: ${kanji.onyomi.join(', ')}',
+                    style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+                  ),
+                if (kanji.kunyomi.isNotEmpty)
+                  Text(
+                    'Kun\'yomi: ${kanji.kunyomi.join(', ')}',
+                    style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+                  ),
+                if (kanji.onyomi.isEmpty && kanji.kunyomi.isEmpty)
+                  Text(
+                    'No readings available.',
+                    style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+                  ),
+                const SizedBox(height: 16),
+                Divider(color: Theme.of(context).colorScheme.onSurfaceVariant),
+                const SizedBox(height: 16),
                 Text(
-                  'On\'yomi: ${kanji.onyomi.join(', ')}',
-                  style: const TextStyle(color: Colors.white),
+                  'SRS Scores:',
+                  style: TextStyle(
+                    color: Theme.of(context).colorScheme.onSurface,
+                    fontWeight: FontWeight.bold,
+                  ),
                 ),
-              if (kanji.kunyomi.isNotEmpty)
-                Text(
-                  'Kun\'yomi: ${kanji.kunyomi.join(', ')}',
-                  style: const TextStyle(color: Colors.white),
+                ...srsScores.entries.map(
+                  (entry) => Text(
+                    '  ${entry.key}: ${entry.value}',
+                    style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+                  ),
                 ),
-              if (kanji.onyomi.isEmpty && kanji.kunyomi.isEmpty)
-                const Text(
-                  'No readings available.',
-                  style: const TextStyle(color: Colors.white),
-                ),
-            ],
+              ],
+            ),
           ),
           actions: [
             TextButton(
-              onPressed: () => Navigator.of(context).pop(),
-              child: const Text('Close',
-                  style: TextStyle(color: Colors.blueAccent)),
+              onPressed: () => Navigator.of(dialogContext).pop(),
+              child: Text(
+                'Close',
+                style: TextStyle(color: Theme.of(context).colorScheme.primary),
+              ),
             ),
           ],
         );
@@ -395,9 +505,13 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
   Future<void> _loadDecks() async {
     setState(() => _loading = true);
     try {
-      final repo = Provider.of<DeckRepository>(context, listen: false);
-      await repo.loadApiKey();
-      final apiKey = repo.apiKey;
+      final kanjiRepo = Provider.of<DeckRepository>(context, listen: false);
+      final vocabRepo = Provider.of<VocabDeckRepository>(
+        context,
+        listen: false,
+      );
+      await kanjiRepo.loadApiKey();
+      final apiKey = kanjiRepo.apiKey;
 
       if (apiKey == null || apiKey.isEmpty) {
         setState(() {
@@ -407,16 +521,16 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
         return;
       }
 
-      var kanji = await repo.loadKanji();
+      var kanji = await kanjiRepo.loadKanji();
       if (kanji.isEmpty || kanji.every((k) => k.level == 0)) {
         setState(() => _status = 'Fetching kanji from WaniKani...');
-        kanji = await repo.fetchAndCacheFromWk(apiKey);
+        kanji = await kanjiRepo.fetchAndCacheFromWk(apiKey);
       }
 
-      var vocab = await repo.loadVocabulary();
+      var vocab = await vocabRepo.loadVocabulary();
       if (vocab.isEmpty || vocab.every((v) => v.level == 0)) {
         setState(() => _status = 'Fetching vocabulary from WaniKani...');
-        vocab = await repo.fetchAndCacheVocabularyFromWk(apiKey);
+        vocab = await vocabRepo.fetchAndCacheVocabularyFromWk(apiKey);
       }
 
       _kanjiDeck = kanji;
@@ -458,8 +572,9 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
   @override
   Widget build(BuildContext context) {
     return Scaffold(
-      appBar: _isSelectionMode ? _buildSelectionAppBar() : _buildDefaultAppBar(),
-      backgroundColor: const Color(0xFF121212),
+      appBar: _isSelectionMode
+          ? _buildSelectionAppBar()
+          : _buildDefaultAppBar(),
       body: Column(
         children: [
           Expanded(
@@ -468,17 +583,19 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
               children: [
                 _buildWaniKaniTab(
                   _buildPaginatedView(
-                      _kanjiByLevel,
-                      _kanjiSortedLevels,
-                      _kanjiPageController,
-                      (items) => _buildGridView(items.cast<KanjiItem>())),
+                    _kanjiByLevel,
+                    _kanjiSortedLevels,
+                    _kanjiPageController,
+                    (items) => _buildGridView(items.cast<KanjiItem>()),
+                  ),
                 ),
                 _buildWaniKaniTab(
                   _buildPaginatedView(
-                      _vocabByLevel,
-                      _vocabSortedLevels,
-                      _vocabPageController,
-                      (items) => _buildListView(items.cast<VocabularyItem>())),
+                    _vocabByLevel,
+                    _vocabSortedLevels,
+                    _vocabPageController,
+                    (items) => _buildListView(items.cast<VocabularyItem>()),
+                  ),
                 ),
                 _buildCustomSrsTab(),
               ],
@@ -487,10 +604,24 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
           if (!_isSelectionMode)
             SafeArea(
               top: false,
-              child: _tabController.index < 2 ? _buildLevelSelector() : const SizedBox.shrink(),
+              child: _tabController.index < 2
+                  ? _buildLevelSelector()
+                  : const SizedBox.shrink(),
             ),
         ],
       ),
+      floatingActionButton: _tabController.index == 2
+          ? FloatingActionButton(
+              onPressed: () async {
+                await Navigator.of(
+                  context,
+                ).push(MaterialPageRoute(builder: (_) => AddCardScreen()));
+                if (!mounted) return;
+                _loadCustomDeck();
+              },
+              child: const Icon(Icons.add),
+            )
+          : null,
     );
   }
 
@@ -521,14 +652,8 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
       ),
       title: Text('${_selectedItems.length} selected'),
       actions: [
-        IconButton(
-          icon: const Icon(Icons.select_all),
-          onPressed: _selectAll,
-        ),
-        IconButton(
-          icon: const Icon(Icons.delete),
-          onPressed: _deleteSelected,
-        ),
+        IconButton(icon: const Icon(Icons.select_all), onPressed: _selectAll),
+        IconButton(icon: const Icon(Icons.delete), onPressed: _deleteSelected),
         IconButton(
           icon: Icon(_toggleIntervalIcon),
           onPressed: _toggleIntervalForSelected,
@@ -549,7 +674,8 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
     setState(() {
       if (_selectedItems.length == _customDeck.length) {
         _selectedItems.clear();
-      } else {
+      }
+      else {
         _selectedItems = List.from(_customDeck);
       }
     });
@@ -558,25 +684,30 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
   void _deleteSelected() {
     showDialog(
       context: context,
-      builder: (context) => AlertDialog(
+      builder: (dialogContext) => AlertDialog(
         title: const Text('Delete Selected'),
-        content: Text('Are you sure you want to delete ${_selectedItems.length} cards?'),
+        content: Text(
+          'Are you sure you want to delete ${_selectedItems.length} cards?',
+        ),
         actions: [
           TextButton(
-            onPressed: () => Navigator.of(context).pop(),
+            onPressed: () => Navigator.of(dialogContext).pop(),
             child: const Text('Cancel'),
           ),
           TextButton(
-            onPressed: () async {
-              for (final item in _selectedItems) {
-                await _customDeckRepository.deleteCard(item);
-              }
-              setState(() {
-                _isSelectionMode = false;
-                _selectedItems.clear();
-              });
-              _loadCustomDeck();
-              Navigator.of(context).pop();
+            onPressed: () {
+              Navigator.of(dialogContext).pop();
+              () async {
+                for (final item in _selectedItems) {
+                  await _customDeckRepository.deleteCard(item);
+                }
+                if (!mounted) return;
+                setState(() {
+                  _isSelectionMode = false;
+                  _selectedItems.clear();
+                });
+                _loadCustomDeck();
+              }();
             },
             child: const Text('Delete'),
           ),
@@ -591,7 +722,9 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
     }
     final bool targetState = _selectedItems.any((item) => !item.useInterval);
 
-    final selectedCharacters = _selectedItems.map((item) => item.characters).toSet();
+    final selectedCharacters = _selectedItems
+        .map((item) => item.characters)
+        .toSet();
 
     final List<CustomKanjiItem> updatedItems = [];
     for (final item in _selectedItems) {
@@ -600,8 +733,7 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
         meaning: item.meaning,
         kanji: item.kanji,
         useInterval: targetState,
-        srsLevel: item.srsLevel,
-        nextReview: item.nextReview,
+        srsData: item.srsData,
       );
       updatedItems.add(updatedItem);
     }
@@ -653,26 +785,28 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
                 }
               });
             } else {
-              Navigator.of(context).push(
-                MaterialPageRoute(
-                  builder: (_) => CustomCardDetailsScreen(
-                    item: item,
-                    repository: _customDeckRepository,
-                  ),
-                ),
-              ).then((_) => _loadCustomDeck());
+              Navigator.of(context)
+                  .push(
+                    MaterialPageRoute(
+                      builder: (_) => CustomCardDetailsScreen(
+                        item: item,
+                        repository: _customDeckRepository,
+                      ),
+                    ),
+                  )
+                  .then((_) => _loadCustomDeck());
             }
           },
           child: Card(
             shape: RoundedRectangleBorder(
               side: isSelected
-                  ? const BorderSide(color: Colors.blue, width: 2.0)
+                  ? BorderSide(color: Theme.of(context).colorScheme.primary, width: 2.0)
                   : BorderSide.none,
               borderRadius: BorderRadius.circular(12.0),
             ),
             color: isSelected
-                ? Colors.blue.withOpacity(0.5)
-                : const Color(0xFF1E1E1E),
+                ? Theme.of(context).colorScheme.primary.withAlpha((255 * 0.5).round())
+                : Theme.of(context).colorScheme.surfaceContainer,
             child: Stack(
               children: [
                 Padding(
@@ -683,20 +817,37 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
                       FittedBox(
                         fit: BoxFit.scaleDown,
                         child: Text(
-                          item.kanji ?? item.characters,
-                          style: const TextStyle(fontSize: 32, color: Colors.white),
+                          item.kanji?.isNotEmpty == true
+                              ? item.kanji!
+                              : item.characters,
+                          style: TextStyle(
+                            fontSize: 32,
+                            color: Theme.of(context).colorScheme.onSurface,
+                          ),
                           textAlign: TextAlign.center,
                         ),
                       ),
                       const SizedBox(height: 8),
                       Text(
                         item.meaning,
-                        style: const TextStyle(color: Colors.grey, fontSize: 16),
+                        style: TextStyle(
+                          color: Theme.of(context).colorScheme.onSurfaceVariant,
+                          fontSize: 16,
+                        ),
                         textAlign: TextAlign.center,
                         overflow: TextOverflow.ellipsis,
                       ),
                       const SizedBox(height: 8),
-                      _buildSrsIndicator(item.srsLevel),
+                      Builder(
+                        builder: (context) {
+                          final avgSrs =
+                              (item.srsData.japaneseToEnglish +
+                                  item.srsData.englishToJapanese +
+                                  item.srsData.listeningComprehension) /
+                              3;
+                          return _buildSrsIndicator(avgSrs.round());
+                        },
+                      ),
                     ],
                   ),
                 ),
@@ -704,11 +855,7 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
                   Positioned(
                     top: 4,
                     right: 4,
-                    child: Icon(
-                      Icons.timer,
-                      color: Colors.green,
-                      size: 16,
-                    ),
+                    child: Icon(Icons.timer, color: Theme.of(context).colorScheme.tertiary, size: 16),
                   ),
               ],
             ),
@@ -719,3 +866,197 @@ class _BrowseScreenState extends State<BrowseScreen> with SingleTickerProviderSt
     );
   }
 }
+
+class _VocabDetailsDialog extends StatefulWidget {
+  final VocabularyItem vocab;
+
+  const _VocabDetailsDialog({required this.vocab});
+
+  @override
+  State<_VocabDetailsDialog> createState() => _VocabDetailsDialogState();
+}
+
+class _VocabDetailsDialogState extends State<_VocabDetailsDialog> {
+  List<Widget> _exampleSentences = [const CircularProgressIndicator()];
+
+  @override
+  void initState() {
+    super.initState();
+    _fetchExampleSentences();
+  }
+
+  Future<void> _fetchExampleSentences() async {
+    final theme = Theme.of(context);
+    try {
+      final uri = Uri.parse(
+        'https://jisho.org/api/v1/search/words?keyword=${Uri.encodeComponent(widget.vocab.characters)}',
+      );
+      final response = await http.get(uri);
+      if (response.statusCode == 200) {
+        final data = jsonDecode(utf8.decode(response.bodyBytes));
+        final sentences = <Widget>[];
+        if (data['data'] != null && (data['data'] as List).isNotEmpty) {
+          for (final result in data['data']) {
+            if (result['japanese'] != null &&
+                (result['japanese'] as List).isNotEmpty &&
+                result['senses'] != null &&
+                (result['senses'] as List).isNotEmpty) {
+              final japaneseWord =
+                  result['japanese'][0]['word'] ??
+                  result['japanese'][0]['reading'];
+              final englishDefinition =
+                  result['senses'][0]['english_definitions'].join(', ');
+              if (japaneseWord != null && englishDefinition != null) {
+                sentences.add(
+                  Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Text(
+                        japaneseWord,
+                        style: TextStyle(color: theme.colorScheme.onSurface),
+                      ),
+                      Text(
+                        englishDefinition,
+                        style: TextStyle(color: theme.colorScheme.onSurfaceVariant),
+                      ),
+                      const SizedBox(height: 8),
+                    ],
+                  ),
+                );
+              }
+            }
+          }
+        }
+        if (sentences.isEmpty) {
+          sentences.add(
+            Text(
+              'No example sentences found.',
+              style: TextStyle(color: theme.colorScheme.onSurface),
+            ),
+          );
+        }
+        if (mounted) {
+          setState(() {
+            _exampleSentences = sentences;
+          });
+        }
+      } else {
+        if (mounted) {
+          setState(() {
+            _exampleSentences = [
+              Text(
+                'Failed to load example sentences.',
+                style: TextStyle(color: theme.colorScheme.error),
+              ),
+            ];
+          });
+        }
+      }
+    } catch (e) {
+      if (mounted) {
+        setState(() {
+          _exampleSentences = [
+            Text(
+              'Error loading example sentences.',
+              style: TextStyle(color: theme.colorScheme.error),
+            ),
+          ];
+        });
+      }
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final srsScores = <String, int>{'JP -> EN': 0, 'EN -> JP': 0, 'Audio': 0};
+
+    for (final entry in widget.vocab.srsItems.entries) {
+      final srsItem = entry.value;
+      switch (srsItem.quizMode) {
+        case QuizMode.vocabToEnglish:
+          srsScores['JP -> EN'] = srsItem.srsStage;
+          break;
+        case QuizMode.englishToVocab:
+          srsScores['EN -> JP'] = srsItem.srsStage;
+          break;
+        case QuizMode.audioToEnglish:
+          srsScores['Audio'] = srsItem.srsStage;
+          break;
+        default:
+          break;
+      }
+    }
+
+    return SingleChildScrollView(
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            'Level: ${widget.vocab.level}',
+            style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+          ),
+          const SizedBox(height: 16),
+          if (widget.vocab.meanings.isNotEmpty)
+            Text(
+              'Meanings: ${widget.vocab.meanings.join(', ')}',
+              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+            ),
+          const SizedBox(height: 16),
+          if (widget.vocab.readings.isNotEmpty)
+            Text(
+              'Readings: ${widget.vocab.readings.join(', ')}',
+              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+            ),
+          const SizedBox(height: 16),
+          Divider(color: Theme.of(context).colorScheme.onSurfaceVariant),
+          const SizedBox(height: 16),
+          Text(
+            'SRS Scores:',
+            style: TextStyle(color: Theme.of(context).colorScheme.onSurface, fontWeight: FontWeight.bold),
+          ),
+          ...srsScores.entries.map(
+            (entry) => Text(
+              '  ${entry.key}: ${entry.value}',
+              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+            ),
+          ),
+          const SizedBox(height: 16),
+          Divider(color: Theme.of(context).colorScheme.onSurfaceVariant),
+          const SizedBox(height: 16),
+          Text(
+            'Example Sentences:',
+            style: TextStyle(color: Theme.of(context).colorScheme.onSurface, fontWeight: FontWeight.bold),
+          ),
+          ..._exampleSentences,
+        ],
+      ),
+    );
+  }
+}
+
+void _showVocabDetailsDialog(BuildContext context, VocabularyItem vocab) {
+  showDialog(
+    context: context,
+    builder: (dialogContext) {
+      return AlertDialog(
+        backgroundColor: Theme.of(context).colorScheme.surfaceContainer,
+        title: Text(
+          'Details for ${vocab.characters}',
+          style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
+        ),
+        content: _VocabDetailsDialog(vocab: vocab),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.of(dialogContext).pop(),
+            child: Text(
+              'Close',
+              style: TextStyle(color: Theme.of(context).colorScheme.primary),
+            ),
+          ),
+        ],
+      );
+    },
+  );
+}
+

lib/src/screens/custom_card_details_screen.dart

@@ -6,8 +6,11 @@ class CustomCardDetailsScreen extends StatefulWidget {
   final CustomKanjiItem item;
   final CustomDeckRepository repository;
 
-  const CustomCardDetailsScreen(
-      {super.key, required this.item, required this.repository});
+  const CustomCardDetailsScreen({
+    super.key,
+    required this.item,
+    required this.repository,
+  });
 
   @override
   State<CustomCardDetailsScreen> createState() =>
@@ -19,7 +22,6 @@ class _CustomCardDetailsScreenState extends State<CustomCardDetailsScreen> {
   late TextEditingController _englishController;
   late TextEditingController _kanjiController;
   late bool _useInterval;
-  late int _srsLevel;
 
   @override
   void initState() {
@@ -28,7 +30,6 @@ class _CustomCardDetailsScreenState extends State<CustomCardDetailsScreen> {
     _englishController = TextEditingController(text: widget.item.meaning);
     _kanjiController = TextEditingController(text: widget.item.kanji);
     _useInterval = widget.item.useInterval;
-    _srsLevel = widget.item.srsLevel;
   }
 
   @override
@@ -43,10 +44,11 @@ class _CustomCardDetailsScreenState extends State<CustomCardDetailsScreen> {
     final updatedItem = CustomKanjiItem(
       characters: _japaneseController.text,
       meaning: _englishController.text,
-      kanji: _kanjiController.text,
+      kanji: _kanjiController.text.trim().isNotEmpty
+          ? _kanjiController.text.trim()
+          : null,
       useInterval: _useInterval,
-      srsLevel: _srsLevel,
-      nextReview: widget.item.nextReview,
+      srsData: widget.item.srsData,
     );
     widget.repository.updateCard(updatedItem);
     Navigator.of(context).pop(true);
@@ -82,10 +84,7 @@ class _CustomCardDetailsScreenState extends State<CustomCardDetailsScreen> {
       appBar: AppBar(
         title: const Text('Edit Card'),
         actions: [
-          IconButton(
-            icon: const Icon(Icons.delete),
-            onPressed: _deleteCard,
-          ),
+          IconButton(icon: const Icon(Icons.delete), onPressed: _deleteCard),
         ],
       ),
       body: Padding(
@@ -113,7 +112,20 @@ class _CustomCardDetailsScreenState extends State<CustomCardDetailsScreen> {
                 });
               },
             ),
-            Text('SRS Level: $_srsLevel'),
+            const SizedBox(height: 20),
+            const Text(
+              'SRS Levels',
+              style: TextStyle(fontWeight: FontWeight.bold),
+            ),
+            Text(
+              'Jpn→Eng: ${widget.item.srsData.japaneseToEnglish} (Next review: ${widget.item.srsData.japaneseToEnglishNextReview?.toString() ?? 'N/A'})',
+            ),
+            Text(
+              'Eng→Jpn: ${widget.item.srsData.englishToJapanese} (Next review: ${widget.item.srsData.englishToJapaneseNextReview?.toString() ?? 'N/A'})',
+            ),
+            Text(
+              'Listening: ${widget.item.srsData.listeningComprehension} (Next review: ${widget.item.srsData.listeningComprehensionNextReview?.toString() ?? 'N/A'})',
+            ),
             const SizedBox(height: 20),
             ElevatedButton(
               onPressed: _saveChanges,

lib/src/screens/custom_quiz_screen.dart

@@ -3,14 +3,20 @@ import 'dart:math';
 import 'package:flutter_tts/flutter_tts.dart';
 import '../models/custom_kanji_item.dart';
 import '../widgets/options_grid.dart';
+import '../widgets/kanji_card.dart';
 
-enum CustomQuizMode { japaneseToEnglish, englishToJapanese, listeningComprehension }
+enum CustomQuizMode {
+  japaneseToEnglish,
+  englishToJapanese,
+  listeningComprehension,
+}
 
 class CustomQuizScreen extends StatefulWidget {
   final List<CustomKanjiItem> deck;
   final CustomQuizMode quizMode;
   final Function(CustomKanjiItem) onCardReviewed;
   final bool useKanji;
+  final bool isActive;
 
   const CustomQuizScreen({
     super.key,
@@ -18,6 +24,7 @@ class CustomQuizScreen extends StatefulWidget {
     required this.quizMode,
     required this.onCardReviewed,
     required this.useKanji,
+    required this.isActive,
   });
 
   @override
@@ -34,6 +41,7 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
   late FlutterTts _flutterTts;
   late AnimationController _shakeController;
   late Animation<double> _shakeAnimation;
+  final List<String> _incorrectlyAnsweredItems = [];
 
   @override
   void initState() {
@@ -49,16 +57,24 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
       vsync: this,
     );
     _shakeAnimation = Tween<double>(begin: 0, end: 1).animate(
-      CurvedAnimation(
-        parent: _shakeController,
-        curve: Curves.elasticIn,
-      ),
+      CurvedAnimation(parent: _shakeController, curve: Curves.elasticIn),
     );
   }
 
   @override
   void didUpdateWidget(CustomQuizScreen oldWidget) {
     super.didUpdateWidget(oldWidget);
+    if (widget.deck != oldWidget.deck && !widget.isActive) {
+      setState(() {
+        _shuffledDeck = widget.deck.toList()..shuffle();
+        _currentIndex = 0;
+        _answered = false;
+        _correct = null;
+        if (_shuffledDeck.isNotEmpty) {
+          _generateOptions();
+        }
+      });
+    }
     if (widget.useKanji != oldWidget.useKanji) {
       setState(() {
         _generateOptions();
@@ -67,7 +83,8 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
   }
 
   void playAudio() {
-    if (widget.quizMode == CustomQuizMode.listeningComprehension) {
+    if (widget.quizMode == CustomQuizMode.listeningComprehension &&
+        _currentIndex < _shuffledDeck.length) {
       _speak(_shuffledDeck[_currentIndex].characters);
     }
   }
@@ -75,9 +92,6 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
   void _initTts() async {
     _flutterTts = FlutterTts();
     await _flutterTts.setLanguage("ja-JP");
-    if (_shuffledDeck.isNotEmpty && widget.quizMode == CustomQuizMode.listeningComprehension) {
-      _speak(_shuffledDeck[_currentIndex].characters);
-    }
   }
 
   @override
@@ -89,69 +103,159 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
 
   void _generateOptions() {
     final currentItem = _shuffledDeck[_currentIndex];
-    if (widget.quizMode == CustomQuizMode.listeningComprehension || widget.quizMode == CustomQuizMode.japaneseToEnglish) {
+    if (widget.quizMode == CustomQuizMode.listeningComprehension ||
+        widget.quizMode == CustomQuizMode.japaneseToEnglish) {
       _options = [currentItem.meaning];
     } else {
-      _options = [widget.useKanji && currentItem.kanji != null ? currentItem.kanji! : currentItem.characters];
+      _options = [
+        widget.useKanji && currentItem.kanji != null
+            ? currentItem.kanji!
+            : currentItem.characters,
+      ];
     }
     final otherItems = widget.deck
         .where((item) => item.characters != currentItem.characters)
         .toList();
     otherItems.shuffle();
     for (var i = 0; i < min(3, otherItems.length); i++) {
-      if (widget.quizMode == CustomQuizMode.listeningComprehension || widget.quizMode == CustomQuizMode.japaneseToEnglish) {
+      if (widget.quizMode == CustomQuizMode.listeningComprehension ||
+          widget.quizMode == CustomQuizMode.japaneseToEnglish) {
         _options.add(otherItems[i].meaning);
       } else {
-        _options.add(widget.useKanji && otherItems[i].kanji != null ? otherItems[i].kanji! : otherItems[i].characters);
+        _options.add(
+          widget.useKanji && otherItems[i].kanji != null
+              ? otherItems[i].kanji!
+              : otherItems[i].characters,
+        );
       }
     }
     _options.shuffle();
   }
 
-  void _checkAnswer(String answer) {
+  void _checkAnswer(String answer) async {
     final currentItem = _shuffledDeck[_currentIndex];
     final correctAnswer = (widget.quizMode == CustomQuizMode.englishToJapanese)
-        ? (widget.useKanji && currentItem.kanji != null ? currentItem.kanji! : currentItem.characters)
+        ? (widget.useKanji && currentItem.kanji != null
+              ? currentItem.kanji!
+              : currentItem.characters)
         : currentItem.meaning;
     final isCorrect = answer == correctAnswer;
 
     if (currentItem.useInterval) {
-      if (isCorrect) {
-        currentItem.srsLevel++;
-        final interval = pow(2, currentItem.srsLevel).toInt();
-        currentItem.nextReview = DateTime.now().add(Duration(hours: interval));
-      } else {
-        currentItem.srsLevel = max(0, currentItem.srsLevel - 1);
-        currentItem.nextReview = DateTime.now().add(const Duration(hours: 1));
+      int currentSrsLevel;
+      switch (widget.quizMode) {
+        case CustomQuizMode.japaneseToEnglish:
+          currentSrsLevel = currentItem.srsData.japaneseToEnglish;
+          break;
+        case CustomQuizMode.englishToJapanese:
+          currentSrsLevel = currentItem.srsData.englishToJapanese;
+          break;
+        case CustomQuizMode.listeningComprehension:
+          currentSrsLevel = currentItem.srsData.listeningComprehension;
+          break;
       }
+
+      if (isCorrect) {
+        if (_incorrectlyAnsweredItems.contains(currentItem.characters)) {
+          _incorrectlyAnsweredItems.remove(currentItem.characters);
+        } else {
+          currentSrsLevel++;
+        }
+        final interval = pow(2, currentSrsLevel).toInt();
+        final newNextReview = DateTime.now().add(Duration(hours: interval));
+        switch (widget.quizMode) {
+          case CustomQuizMode.japaneseToEnglish:
+            currentItem.srsData.japaneseToEnglishNextReview = newNextReview;
+            break;
+          case CustomQuizMode.englishToJapanese:
+            currentItem.srsData.englishToJapaneseNextReview = newNextReview;
+            break;
+          case CustomQuizMode.listeningComprehension:
+            currentItem.srsData.listeningComprehensionNextReview =
+                newNextReview;
+            break;
+        }
+      } else {
+        if (!_incorrectlyAnsweredItems.contains(currentItem.characters)) {
+          _incorrectlyAnsweredItems.add(currentItem.characters);
+        }
+        currentSrsLevel = max(0, currentSrsLevel - 1);
+        final newNextReview = DateTime.now().add(const Duration(hours: 1));
+        switch (widget.quizMode) {
+          case CustomQuizMode.japaneseToEnglish:
+            currentItem.srsData.japaneseToEnglishNextReview = newNextReview;
+            break;
+          case CustomQuizMode.englishToJapanese:
+            currentItem.srsData.englishToJapaneseNextReview = newNextReview;
+            break;
+          case CustomQuizMode.listeningComprehension:
+            currentItem.srsData.listeningComprehensionNextReview =
+                newNextReview;
+            break;
+        }
+      }
+
+      switch (widget.quizMode) {
+        case CustomQuizMode.japaneseToEnglish:
+          currentItem.srsData.japaneseToEnglish = currentSrsLevel;
+          break;
+        case CustomQuizMode.englishToJapanese:
+          currentItem.srsData.englishToJapanese = currentSrsLevel;
+          break;
+        case CustomQuizMode.listeningComprehension:
+          currentItem.srsData.listeningComprehension = currentSrsLevel;
+          break;
+      }
+
       widget.onCardReviewed(currentItem);
     }
 
-    setState(() {
-      _answered = true;
-      _correct = isCorrect;
-    });
+    final correctDisplay = (widget.quizMode == CustomQuizMode.englishToJapanese)
+        ? (widget.useKanji && currentItem.kanji != null
+              ? currentItem.kanji!
+              : currentItem.characters)
+        : currentItem.meaning;
+
+    final snack = SnackBar(
+      content: Text(
+        isCorrect ? 'Correct!' : 'Wrong — correct: $correctDisplay',
+        style: TextStyle(
+          color: isCorrect ? Theme.of(context).colorScheme.tertiary : Theme.of(context).colorScheme.error,
+          fontWeight: FontWeight.bold,
+        ),
+      ),
+      backgroundColor: Theme.of(context).colorScheme.surfaceContainerHighest,
+      duration: const Duration(milliseconds: 900),
+    );
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(snack);
+    }
 
     if (isCorrect) {
-      if (widget.quizMode == CustomQuizMode.japaneseToEnglish ||
-          widget.quizMode == CustomQuizMode.listeningComprehension) {
-        _speak(currentItem.characters);
+      if (widget.quizMode == CustomQuizMode.japaneseToEnglish) {
+        await _speak(currentItem.characters);
       }
+      await Future.delayed(const Duration(milliseconds: 500));
     } else {
       _shakeController.forward(from: 0);
+      await Future.delayed(const Duration(milliseconds: 900));
     }
+
+    _nextQuestion();
   }
 
   void _nextQuestion() {
     setState(() {
-      _currentIndex = (_currentIndex + 1) % _shuffledDeck.length;
+      _currentIndex++;
       _answered = false;
       _correct = null;
-      _generateOptions();
+      if (_currentIndex < _shuffledDeck.length) {
+        _generateOptions();
+        if (widget.quizMode == CustomQuizMode.listeningComprehension) {
+          _speak(_shuffledDeck[_currentIndex].characters);
+        }
+      }
     });
-    if (widget.quizMode == CustomQuizMode.listeningComprehension) {
-      _speak(_shuffledDeck[_currentIndex].characters);
-    }
   }
 
   Future<void> _speak(String text) async {
@@ -166,63 +270,76 @@ class CustomQuizScreenState extends State<CustomQuizScreen>
 
   @override
   Widget build(BuildContext context) {
-    if (_shuffledDeck.isEmpty) {
-      return const Center(
-        child: Text('Review session complete!'),
-      );
+    if (_shuffledDeck.isEmpty || _currentIndex >= _shuffledDeck.length) {
+      return Center(child: Text('Review session complete!', style: TextStyle(color: Theme.of(context).colorScheme.onSurface)));
     }
 
     final currentItem = _shuffledDeck[_currentIndex];
     final question = (widget.quizMode == CustomQuizMode.englishToJapanese)
         ? currentItem.meaning
-        : (widget.useKanji && currentItem.kanji != null ? currentItem.kanji! : currentItem.characters);
+        : (widget.useKanji && currentItem.kanji != null
+              ? currentItem.kanji!
+              : currentItem.characters);
 
-    return Center(
+    Widget promptWidget;
+    if (widget.quizMode == CustomQuizMode.listeningComprehension) {
+      promptWidget = IconButton(
+        icon: const Icon(Icons.volume_up, size: 64),
+        onPressed: () => _speak(currentItem.characters),
+      );
+    } else {
+      promptWidget = GestureDetector(
+        onTap: () => _speak(question),
+        child: Text(
+          question,
+          style: TextStyle(fontSize: 48, color: Theme.of(context).colorScheme.onSurface),
+          textAlign: TextAlign.center,
+        ),
+      );
+    }
+
+    return Padding(
+      padding: const EdgeInsets.all(16.0),
       child: Column(
-        mainAxisAlignment: MainAxisAlignment.center,
         children: [
-          if (widget.quizMode == CustomQuizMode.listeningComprehension)
-            IconButton(
-              icon: const Icon(Icons.volume_up, size: 64),
-              onPressed: () => _speak(currentItem.characters),
-            )
-          else
-            GestureDetector(
-              onTap: () => _speak(question),
-              child: Text(
-                question,
-                style: const TextStyle(fontSize: 48),
-                textAlign: TextAlign.center,
+          const SizedBox(height: 18),
+          Expanded(
+            flex: 3,
+            child: Center(
+              child: ConstrainedBox(
+                constraints: const BoxConstraints(
+                  minWidth: 0,
+                  maxWidth: 500,
+                  minHeight: 150,
+                ),
+                child: KanjiCard(characterWidget: promptWidget, subtitle: ''),
               ),
             ),
-          const SizedBox(height: 32),
-          if (_answered)
-            Text(
-              _correct! ? 'Correct!' : 'Incorrect, try again!',
-              style: TextStyle(
-                fontSize: 24,
-                color: _correct! ? Colors.green : Colors.red,
-              ),
-            ),
-          const SizedBox(height: 32),
-          AnimatedBuilder(
-            animation: _shakeAnimation,
-            builder: (context, child) {
-              return Transform.translate(
-                offset: Offset(_shakeAnimation.value * 10, 0),
-                child: child,
-              );
-            },
-            child: OptionsGrid(
-              options: _options,
-              onSelected: _onOptionSelected,
-            ),
           ),
-          if (_answered && _correct!)
-            ElevatedButton(
-              onPressed: _nextQuestion,
-              child: const Text('Next'),
+          const SizedBox(height: 12),
+          SafeArea(
+            top: false,
+            child: Column(
+              children: [
+                AnimatedBuilder(
+                  animation: _shakeAnimation,
+                  builder: (context, child) {
+                    return Transform.translate(
+                      offset: Offset(_shakeAnimation.value * 10, 0),
+                      child: child,
+                    );
+                  },
+                  child: OptionsGrid(
+                    options: _options,
+                    onSelected: _onOptionSelected,
+                    correctAnswers: [],
+                    showResult: false,
+                    isDisabled: false,
+                  ),
+                ),
+              ],
             ),
+          ),
         ],
       ),
     );

lib/src/screens/custom_srs_screen.dart

@@ -1,7 +1,6 @@
 import 'package:flutter/material.dart';
 import '../models/custom_kanji_item.dart';
 import '../services/custom_deck_repository.dart';
-import 'add_card_screen.dart';
 import 'custom_quiz_screen.dart';
 
 class CustomSrsScreen extends StatefulWidget {
@@ -11,11 +10,11 @@ class CustomSrsScreen extends StatefulWidget {
   State<CustomSrsScreen> createState() => _CustomSrsScreenState();
 }
 
-class _CustomSrsScreenState extends State<CustomSrsScreen> with SingleTickerProviderStateMixin {
+class _CustomSrsScreenState extends State<CustomSrsScreen>
+    with SingleTickerProviderStateMixin {
   late TabController _tabController;
   final _deckRepository = CustomDeckRepository();
   List<CustomKanjiItem> _deck = [];
-  List<CustomKanjiItem> _reviewDeck = [];
   bool _useKanji = false;
   final _quizScreenKeys = [
     GlobalKey<CustomQuizScreenState>(),
@@ -45,26 +44,18 @@ class _CustomSrsScreenState extends State<CustomSrsScreen> with SingleTickerProv
 
   Future<void> _loadDeck() async {
     final deck = await _deckRepository.getCustomDeck();
-    final now = DateTime.now();
-    final reviewDeck = deck.where((item) {
-      if (!item.useInterval) {
-        return true;
-      }
-      return item.nextReview == null || item.nextReview!.isBefore(now);
-    }).toList();
-
     setState(() {
       _deck = deck;
-      _reviewDeck = reviewDeck;
     });
   }
 
   Future<void> _updateCard(CustomKanjiItem item) async {
-    final index = _deck.indexWhere((element) => element.characters == item.characters);
+    final index = _deck.indexWhere(
+      (element) => element.characters == item.characters,
+    );
     if (index != -1) {
       setState(() {
         _deck[index] = item;
-        _reviewDeck.removeWhere((element) => element.characters == item.characters);
       });
       await _deckRepository.saveDeck(_deck);
     }
@@ -72,6 +63,30 @@ class _CustomSrsScreenState extends State<CustomSrsScreen> with SingleTickerProv
 
   @override
   Widget build(BuildContext context) {
+    final now = DateTime.now();
+    final jpnToEngReviewDeck = _deck.where((item) {
+      if (!item.useInterval) return true;
+      return item.srsData.japaneseToEnglishNextReview == null ||
+          item.srsData.japaneseToEnglishNextReview!.isBefore(now);
+    }).toList();
+
+    final engToJpnReviewDeck = _deck.where((item) {
+      if (!item.useInterval) return true;
+      return item.srsData.englishToJapaneseNextReview == null ||
+          item.srsData.englishToJapaneseNextReview!.isBefore(now);
+    }).toList();
+
+    final listeningReviewDeck = _deck.where((item) {
+      if (!item.useInterval) return true;
+      return item.srsData.listeningComprehensionNextReview == null ||
+          item.srsData.listeningComprehensionNextReview!.isBefore(now);
+    }).toList();
+
+    final allDecksEmpty =
+        jpnToEngReviewDeck.isEmpty &&
+        engToJpnReviewDeck.isEmpty &&
+        listeningReviewDeck.isEmpty;
+
     return Scaffold(
       appBar: AppBar(
         title: const Text('Custom SRS'),
@@ -102,43 +117,37 @@ class _CustomSrsScreenState extends State<CustomSrsScreen> with SingleTickerProv
       ),
       body: _deck.isEmpty
           ? const Center(child: Text('Add cards to start quizzing!'))
-          : _reviewDeck.isEmpty
-              ? const Center(child: Text('No cards due for review.'))
-              : TabBarView(
+          : allDecksEmpty
+          ? const Center(child: Text('No cards due for review.'))
+          : TabBarView(
               controller: _tabController,
               children: [
                 CustomQuizScreen(
                   key: _quizScreenKeys[0],
-                  deck: _reviewDeck,
+                  deck: jpnToEngReviewDeck,
                   quizMode: CustomQuizMode.japaneseToEnglish,
                   onCardReviewed: _updateCard,
                   useKanji: _useKanji,
+                  isActive: _tabController.index == 0,
                 ),
                 CustomQuizScreen(
                   key: _quizScreenKeys[1],
-                  deck: _reviewDeck,
+                  deck: engToJpnReviewDeck,
                   quizMode: CustomQuizMode.englishToJapanese,
                   onCardReviewed: _updateCard,
                   useKanji: _useKanji,
+                  isActive: _tabController.index == 1,
                 ),
                 CustomQuizScreen(
                   key: _quizScreenKeys[2],
-                  deck: _reviewDeck,
+                  deck: listeningReviewDeck,
                   quizMode: CustomQuizMode.listeningComprehension,
                   onCardReviewed: _updateCard,
                   useKanji: _useKanji,
+                  isActive: _tabController.index == 2,
                 ),
               ],
             ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: () async {
-          await Navigator.of(context).push(
-            MaterialPageRoute(builder: (_) => const AddCardScreen()),
-          );
-          _loadDeck();
-        },
-        child: const Icon(Icons.add),
-      ),
     );
   }
 }

lib/src/screens/home_screen.dart

@@ -3,6 +3,7 @@ import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import '../models/kanji_item.dart';
+import '../models/srs_item.dart';
 import '../services/deck_repository.dart';
 import '../services/distractor_generator.dart';
 import '../widgets/kanji_card.dart';
@@ -18,6 +19,18 @@ class _ReadingInfo {
   _ReadingInfo(this.correctReadings, this.hint);
 }
 
+class _QuizState {
+  KanjiItem? current;
+  List<String> options = [];
+  List<String> correctAnswers = [];
+  String readingHint = '';
+  int score = 0;
+  int asked = 0;
+  Key key = UniqueKey();
+  String? selectedOption;
+  bool showResult = false;
+}
+
 class HomeScreen extends StatefulWidget {
   const HomeScreen({super.key, this.distractorGenerator});
 
@@ -27,21 +40,20 @@ class HomeScreen extends StatefulWidget {
   State<HomeScreen> createState() => _HomeScreenState();
 }
 
-class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateMixin {
+class _HomeScreenState extends State<HomeScreen>
+    with SingleTickerProviderStateMixin {
   late TabController _tabController;
   List<KanjiItem> _deck = [];
   bool _loading = false;
+  bool _isAnswering = false;
   String _status = 'Loading deck...';
   late final DistractorGenerator _dg;
   final Random _random = Random();
   final _audioPlayer = AudioPlayer();
 
-  KanjiItem? _current;
-  List<String> _options = [];
-  List<String> _correctAnswers = [];
-  String _readingHint = '';
-  int _score = 0;
-  int _asked = 0;
+  final _quizStates = [_QuizState(), _QuizState(), _QuizState()];
+  _QuizState get _currentQuizState => _quizStates[_tabController.index];
+
   bool _playCorrectSound = true;
   bool _apiKeyMissing = false;
 
@@ -51,7 +63,6 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
     _tabController = TabController(length: 3, vsync: this);
     _tabController.addListener(() {
       setState(() {});
-      _nextQuestion();
     });
     _dg = widget.distractorGenerator ?? DistractorGenerator();
     _loadSettings();
@@ -105,7 +116,9 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
         _apiKeyMissing = false;
       });
 
-      _nextQuestion();
+      for (var i = 0; i < _tabController.length; i++) {
+        _nextQuestion(i);
+      }
     } catch (e) {
       setState(() {
         _status = 'Error: $e';
@@ -135,8 +148,8 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
     return _ReadingInfo(readingsList, hint);
   }
 
-  QuizMode get _mode {
-    switch (_tabController.index) {
+  QuizMode _modeForIndex(int index) {
+    switch (index) {
       case 0:
         return QuizMode.kanjiToEnglish;
       case 1:
@@ -148,127 +161,168 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
     }
   }
 
-  void _nextQuestion() {
+  void _nextQuestion([int? index]) {
     if (_deck.isEmpty) return;
 
+    final quizState = _quizStates[index ?? _tabController.index];
+    final mode = _modeForIndex(index ?? _tabController.index);
+
     _deck.sort((a, b) {
-      String srsKey(KanjiItem item) {
-        var key = _mode.toString();
-        if (_mode == QuizMode.reading) {
-          if (item.onyomi.isNotEmpty && item.kunyomi.isNotEmpty) {
-            key += _random.nextBool() ? 'onyomi' : 'kunyomi';
-          } else if (item.onyomi.isNotEmpty) {
-            key += 'onyomi';
-          } else {
-            key += 'kunyomi';
+      int getSrsStage(KanjiItem item) {
+        if (mode == QuizMode.reading) {
+          final onyomiStage =
+              item.srsItems['${QuizMode.reading}onyomi']?.srsStage;
+          final kunyomiStage =
+              item.srsItems['${QuizMode.reading}kunyomi']?.srsStage;
+
+          if (onyomiStage != null && kunyomiStage != null) {
+            return min(onyomiStage, kunyomiStage);
           }
+          return onyomiStage ?? kunyomiStage ?? 0;
         }
-        return key;
+        return item.srsItems[mode.toString()]?.srsStage ?? 0;
       }
 
-      final aSrsItem = a.srsItems[srsKey(a)];
-      final bSrsItem = b.srsItems[srsKey(b)];
+      DateTime getLastAsked(KanjiItem item) {
+        if (mode == QuizMode.reading) {
+          final onyomiLastAsked =
+              item.srsItems['${QuizMode.reading}onyomi']?.lastAsked;
+          final kunyomiLastAsked =
+              item.srsItems['${QuizMode.reading}kunyomi']?.lastAsked;
 
-      final aStage = aSrsItem?.srsStage ?? 0;
-      final bStage = bSrsItem?.srsStage ?? 0;
+          if (onyomiLastAsked != null && kunyomiLastAsked != null) {
+            return onyomiLastAsked.isBefore(kunyomiLastAsked)
+                ? onyomiLastAsked
+                : kunyomiLastAsked;
+          }
+          return onyomiLastAsked ??
+              kunyomiLastAsked ??
+              DateTime.fromMillisecondsSinceEpoch(0);
+        }
+        return item.srsItems[mode.toString()]?.lastAsked ??
+            DateTime.fromMillisecondsSinceEpoch(0);
+      }
+
+      final aStage = getSrsStage(a);
+      final bStage = getSrsStage(b);
 
       if (aStage != bStage) {
         return aStage.compareTo(bStage);
       }
 
-      final aLastAsked =
-          aSrsItem?.lastAsked ?? DateTime.fromMillisecondsSinceEpoch(0);
-      final bLastAsked =
-          bSrsItem?.lastAsked ?? DateTime.fromMillisecondsSinceEpoch(0);
+      final aLastAsked = getLastAsked(a);
+      final bLastAsked = getLastAsked(b);
 
-      if (aLastAsked != bLastAsked) {
-        return aLastAsked.compareTo(bLastAsked);
-      }
-
-      return _random.nextDouble().compareTo(_random.nextDouble());
+      return aLastAsked.compareTo(bLastAsked);
     });
 
-    _current = _deck.first;
+    quizState.current = _deck.first;
+    quizState.key = UniqueKey();
 
-    _correctAnswers = [];
-    _options = [];
-    _readingHint = '';
+    quizState.correctAnswers = [];
+    quizState.options = [];
+    quizState.readingHint = '';
+    quizState.selectedOption = null;
+    quizState.showResult = false;
 
-    switch (_mode) {
+    switch (mode) {
       case QuizMode.kanjiToEnglish:
-        _correctAnswers = [_current!.meanings.first];
-        _options = [
-          _correctAnswers.first,
-          ..._dg.generateMeanings(_current!, _deck, 3)
-        ].map(_toTitleCase).toList()
-          ..shuffle();
+        quizState.correctAnswers = [quizState.current!.meanings.first];
+        quizState.options = [
+          quizState.correctAnswers.first,
+          ..._dg.generateMeanings(quizState.current!, _deck, 3),
+        ].map(_toTitleCase).toList()..shuffle();
         break;
 
       case QuizMode.englishToKanji:
-        _correctAnswers = [_current!.characters];
-        _options = [
-          _correctAnswers.first,
-          ..._dg.generateKanji(_current!, _deck, 3)
+        quizState.correctAnswers = [quizState.current!.characters];
+        quizState.options = [
+          quizState.correctAnswers.first,
+          ..._dg.generateKanji(quizState.current!, _deck, 3),
         ]..shuffle();
         break;
 
       case QuizMode.reading:
-        final info = _pickReading(_current!);
-        _correctAnswers = info.correctReadings;
-        _readingHint = info.hint;
+        final info = _pickReading(quizState.current!);
+        quizState.correctAnswers = info.correctReadings;
+        quizState.readingHint = info.hint;
 
-        final readingsSource = _readingHint.contains("on'yomi")
+        final readingsSource = quizState.readingHint.contains("on'yomi")
             ? _deck.expand((k) => k.onyomi)
             : _deck.expand((k) => k.kunyomi);
 
-        final distractors = readingsSource
-            .where((r) => !_correctAnswers.contains(r))
-            .toSet()
-            .toList()
-          ..shuffle();
-        _options = ([
-          _correctAnswers[_random.nextInt(_correctAnswers.length)],
-          ...distractors.take(3)
-        ])
-          ..shuffle();
+        final distractors =
+            readingsSource
+                .where((r) => !quizState.correctAnswers.contains(r))
+                .toSet()
+                .toList()
+              ..shuffle();
+        quizState.options = ([
+          quizState.correctAnswers[_random.nextInt(
+            quizState.correctAnswers.length,
+          )],
+          ...distractors.take(3),
+        ])..shuffle();
+        break;
+      default:
+        // Handle other QuizMode cases if necessary, or throw an error
+        // if these modes are not expected in this context.
         break;
     }
 
-    setState(() {});
+    setState(() {
+      _isAnswering = false;
+    });
   }
 
   void _answer(String option) async {
-    final isCorrect = _correctAnswers
+    final quizState = _currentQuizState;
+    final mode = _modeForIndex(_tabController.index);
+    final isCorrect = quizState.correctAnswers
         .map((a) => a.toLowerCase().trim())
         .contains(option.toLowerCase().trim());
 
     final repo = Provider.of<DeckRepository>(context, listen: false);
-    final current = _current!;
+    final current = quizState.current!;
 
     String readingType = '';
-    if (_mode == QuizMode.reading) {
-      readingType = _readingHint.contains("on'yomi") ? 'onyomi' : 'kunyomi';
+    if (mode == QuizMode.reading) {
+      readingType = quizState.readingHint.contains("on'yomi")
+          ? 'onyomi'
+          : 'kunyomi';
     }
-    final srsKey = _mode.toString() + readingType;
+    final srsKey = mode.toString() + readingType;
 
     var srsItem = current.srsItems[srsKey];
     final isNew = srsItem == null;
-    final srsItemForUpdate = srsItem ??=
-        SrsItem(kanjiId: current.id, quizMode: _mode, readingType: readingType);
-    setState(() {
-      _asked += 1;
-      if (isCorrect) {
-        _score += 1;
-        srsItemForUpdate.srsStage += 1;
-        if (_playCorrectSound) {
-          _audioPlayer.play(AssetSource('sfx/confirm.mp3'));
-        }
-      } else {
-        srsItemForUpdate.srsStage = max(0, srsItemForUpdate.srsStage - 1);
+    final srsItemForUpdate = srsItem ??= SrsItem(
+      subjectId: current.id,
+      quizMode: mode,
+      readingType: readingType,
+    );
+
+    quizState.asked += 1;
+
+    quizState.selectedOption = option;
+
+    quizState.showResult = true;
+
+    setState(() {});
+
+    if (isCorrect) {
+      quizState.score += 1;
+      srsItemForUpdate.srsStage += 1;
+      if (_playCorrectSound) {
+        _audioPlayer.play(AssetSource('sfx/confirm.mp3'));
       }
-      srsItemForUpdate.lastAsked = DateTime.now();
-      current.srsItems[srsKey] = srsItemForUpdate;
-    });
+    } else {
+      srsItemForUpdate.srsStage = max(0, srsItemForUpdate.srsStage - 1);
+    }
+    srsItemForUpdate.lastAsked = DateTime.now();
+    current.srsItems[srsKey] = srsItemForUpdate;
+
+    final scaffoldMessenger = ScaffoldMessenger.of(context);
+    final theme = Theme.of(context);
 
     if (isNew) {
       await repo.insertSrsItem(srsItemForUpdate);
@@ -276,28 +330,38 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
       await repo.updateSrsItem(srsItemForUpdate);
     }
 
-    final correctDisplay = (_mode == QuizMode.kanjiToEnglish)
-        ? _toTitleCase(_correctAnswers.first)
-        : (_mode == QuizMode.reading
-            ? _correctAnswers.join(', ')
-            : _correctAnswers.first);
+    final correctDisplay = (mode == QuizMode.kanjiToEnglish)
+        ? _toTitleCase(quizState.correctAnswers.first)
+        : (mode == QuizMode.reading
+              ? quizState.correctAnswers.join(', ')
+              : quizState.correctAnswers.first);
 
     final snack = SnackBar(
       content: Text(
         isCorrect ? 'Correct!' : 'Wrong — correct: $correctDisplay',
         style: TextStyle(
-          color: isCorrect ? Colors.greenAccent : Colors.redAccent,
+          color: isCorrect
+              ? theme.colorScheme.primary
+              : theme.colorScheme.error,
           fontWeight: FontWeight.bold,
         ),
       ),
-      backgroundColor: const Color(0xFF222222),
+      backgroundColor: theme.colorScheme.surfaceContainerHighest,
       duration: const Duration(milliseconds: 900),
     );
     if (mounted) {
-      ScaffoldMessenger.of(context).showSnackBar(snack);
+      scaffoldMessenger.showSnackBar(snack);
     }
 
-    Future.delayed(const Duration(milliseconds: 900), _nextQuestion);
+    setState(() {
+      _isAnswering = true;
+    });
+
+    Future.delayed(const Duration(milliseconds: 900), () {
+      if (mounted) {
+        _nextQuestion();
+      }
+    });
   }
 
   @override
@@ -309,7 +373,12 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
           child: Column(
             mainAxisAlignment: MainAxisAlignment.center,
             children: [
-              const Text('WaniKani API key is not set.', style: TextStyle(color: Colors.white)),
+              Text(
+                'WaniKani API key is not set.',
+                style: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurface,
+                ),
+              ),
               const SizedBox(height: 16),
               ElevatedButton(
                 onPressed: () async {
@@ -326,22 +395,6 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
       );
     }
 
-    String prompt = '';
-    String subtitle = '';
-
-    switch (_mode) {
-      case QuizMode.kanjiToEnglish:
-        prompt = _current?.characters ?? '';
-        break;
-      case QuizMode.englishToKanji:
-        prompt = _current != null ? _toTitleCase(_current!.meanings.first) : '';
-        break;
-      case QuizMode.reading:
-        prompt = _current?.characters ?? '';
-        subtitle = _readingHint;
-        break;
-    }
-
     return Scaffold(
       appBar: AppBar(
         title: const Text('Kanji Quiz'),
@@ -354,64 +407,105 @@ class _HomeScreenState extends State<HomeScreen> with SingleTickerProviderStateM
           ],
         ),
       ),
-      backgroundColor: const Color(0xFF121212),
-      body: Padding(
-        padding: const EdgeInsets.all(16.0),
-        child: Column(
-          children: [
-            Row(
-              children: [
-                Expanded(
-                  child: Text(
-                    _status,
-                    style: const TextStyle(color: Colors.white),
-                  ),
-                ),
-                if (_loading)
-                  const CircularProgressIndicator(color: Colors.blueAccent),
-              ],
-            ),
-            const SizedBox(height: 18),
-            Expanded(
-              flex: 3,
-              child: Center(
-                child: ConstrainedBox(
-                  constraints: const BoxConstraints(
-                    minWidth: 0,
-                    maxWidth: 500,
-                    minHeight: 150,
-                  ),
-                  child: KanjiCard(
-                    characters: prompt,
-                    subtitle: subtitle,
-                    backgroundColor: const Color(0xFF1E1E1E),
-                    textColor: Colors.white,
-                  ),
-                ),
-              ),
-            ),
-            const SizedBox(height: 12),
-            SafeArea(
-              top: false,
-              child: Column(
-                children: [
-                  OptionsGrid(
-                    options: _options,
-                    onSelected: _answer,
-                    buttonColor: const Color(0xFF1E1E1E),
-                    textColor: Colors.white,
-                  ),
-                  const SizedBox(height: 8),
-                  Text(
-                    'Score: $_score / $_asked',
-                    style: const TextStyle(color: Colors.white),
-                  ),
-                ],
-              ),
-            ),
-          ],
-        ),
+      backgroundColor: Theme.of(context).colorScheme.surface,
+      body: TabBarView(
+        controller: _tabController,
+        children: [_buildQuizPage(0), _buildQuizPage(1), _buildQuizPage(2)],
       ),
     );
   }
-}
+
+  Widget _buildQuizPage(int index) {
+    final quizState = _quizStates[index];
+    final mode = _modeForIndex(index);
+
+    String prompt = '';
+    String subtitle = '';
+
+    if (quizState.current != null) {
+      switch (mode) {
+        case QuizMode.kanjiToEnglish:
+          prompt = quizState.current!.characters;
+          break;
+        case QuizMode.englishToKanji:
+          prompt = _toTitleCase(quizState.current!.meanings.first);
+          break;
+        case QuizMode.reading:
+          prompt = quizState.current!.characters;
+          subtitle = quizState.readingHint;
+          break;
+        default:
+          // Handle other QuizMode cases if necessary, or throw an error
+          // if these modes are not expected in this context.
+          break;
+      }
+    }
+
+    return Padding(
+      key: quizState.key,
+      padding: const EdgeInsets.all(16.0),
+      child: Column(
+        children: [
+          Row(
+            children: [
+              Expanded(
+                child: Text(
+                  _status,
+                  style: TextStyle(
+                    color: Theme.of(context).colorScheme.onSurface,
+                  ),
+                ),
+              ),
+              if (_loading)
+                CircularProgressIndicator(
+                  color: Theme.of(context).colorScheme.primary,
+                ),
+            ],
+          ),
+          const SizedBox(height: 18),
+          Expanded(
+            flex: 3,
+            child: Center(
+              child: ConstrainedBox(
+                constraints: const BoxConstraints(
+                  minWidth: 0,
+                  maxWidth: 500,
+                  minHeight: 150,
+                ),
+                child: KanjiCard(
+                  characters: prompt,
+                  subtitle: subtitle,
+                  backgroundColor: Theme.of(context).colorScheme.surface,
+                  textColor: Theme.of(context).colorScheme.onSurface,
+                ),
+              ),
+            ),
+          ),
+          const SizedBox(height: 12),
+          SafeArea(
+            top: false,
+            child: Column(
+              children: [
+                OptionsGrid(
+                  options: quizState.options,
+                  onSelected: _isAnswering ? (option) {} : _answer,
+                  isDisabled: false,
+                  selectedOption: null,
+                  correctAnswers: [],
+                  showResult: false,
+                ),
+                const SizedBox(height: 8),
+                Text(
+                  'Score: ${quizState.score} / ${quizState.asked}',
+                  style: TextStyle(
+                    color: Theme.of(context).colorScheme.onSurface,
+                  ),
+                ),
+              ],
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/src/screens/settings_screen.dart

@@ -1,4 +1,6 @@
 import 'package:flutter/material.dart';
+import 'package:hirameki_srs/src/models/theme_model.dart';
+import 'package:hirameki_srs/src/themes.dart';
 import 'package:provider/provider.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import '../services/deck_repository.dart';
@@ -50,24 +52,26 @@ class _SettingsScreenState extends State<SettingsScreen> {
     await repo.setApiKey(apiKey);
 
     if (mounted) {
-      ScaffoldMessenger.of(context).showSnackBar(
-        const SnackBar(content: Text('API key saved!')),
-      );
+      ScaffoldMessenger.of(
+        context,
+      ).showSnackBar(const SnackBar(content: Text('API key saved!')));
 
-      Navigator.of(context).pushReplacement(
-        MaterialPageRoute(builder: (_) => const HomeScreen()),
-      );
+      Navigator.of(
+        context,
+      ).pushReplacement(MaterialPageRoute(builder: (_) => const HomeScreen()));
     }
   }
 
   @override
   Widget build(BuildContext context) {
+    final themeModel = Provider.of<ThemeModel>(context);
+
     return Scaffold(
-      backgroundColor: const Color(0xFF121212),
+      backgroundColor: Theme.of(context).colorScheme.surface,
       appBar: AppBar(
         title: const Text('Settings'),
-        backgroundColor: const Color(0xFF1F1F1F),
-        foregroundColor: Colors.white,
+        backgroundColor: Theme.of(context).colorScheme.surfaceContainer,
+        foregroundColor: Theme.of(context).colorScheme.onSurface,
       ),
       body: Padding(
         padding: const EdgeInsets.all(16.0),
@@ -76,15 +80,19 @@ class _SettingsScreenState extends State<SettingsScreen> {
             TextField(
               controller: _apiKeyController,
               obscureText: true,
-              style: const TextStyle(color: Colors.white),
+              style: TextStyle(color: Theme.of(context).colorScheme.onSurface),
               decoration: InputDecoration(
                 labelText: 'WaniKani API Key',
-                labelStyle: const TextStyle(color: Colors.grey),
+                labelStyle: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurfaceVariant,
+                ),
                 filled: true,
-                fillColor: const Color(0xFF1E1E1E),
+                fillColor: Theme.of(context).colorScheme.surfaceContainer,
                 border: OutlineInputBorder(
                   borderRadius: BorderRadius.circular(6),
-                  borderSide: const BorderSide(color: Colors.grey),
+                  borderSide: BorderSide(
+                    color: Theme.of(context).colorScheme.onSurfaceVariant,
+                  ),
                 ),
               ),
             ),
@@ -92,16 +100,18 @@ class _SettingsScreenState extends State<SettingsScreen> {
             ElevatedButton(
               onPressed: _saveApiKey,
               style: ElevatedButton.styleFrom(
-                backgroundColor: Colors.blueAccent,
-                foregroundColor: Colors.white,
+                backgroundColor: Theme.of(context).colorScheme.primary,
+                foregroundColor: Theme.of(context).colorScheme.onPrimary,
               ),
               child: const Text('Save & Start Quiz'),
             ),
             const SizedBox(height: 24),
             SwitchListTile(
-              title: const Text(
+              title: Text(
                 'Play audio for vocabulary',
-                style: TextStyle(color: Colors.white),
+                style: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurface,
+                ),
               ),
               value: _playAudio,
               onChanged: (value) async {
@@ -111,18 +121,22 @@ class _SettingsScreenState extends State<SettingsScreen> {
                   _playAudio = value;
                 });
               },
-              activeThumbColor: Colors.blueAccent,
-              inactiveThumbColor: Colors.grey,
-              tileColor: const Color(0xFF1E1E1E),
+              activeThumbColor: Theme.of(context).colorScheme.primary,
+              inactiveThumbColor: Theme.of(
+                context,
+              ).colorScheme.onSurfaceVariant,
+              tileColor: Theme.of(context).colorScheme.surfaceContainer,
               shape: RoundedRectangleBorder(
                 borderRadius: BorderRadius.circular(6),
               ),
             ),
             const SizedBox(height: 12),
             SwitchListTile(
-              title: const Text(
+              title: Text(
                 'Play sound on correct answer',
-                style: TextStyle(color: Colors.white),
+                style: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurface,
+                ),
               ),
               value: _playCorrectSound,
               onChanged: (value) async {
@@ -132,9 +146,50 @@ class _SettingsScreenState extends State<SettingsScreen> {
                   _playCorrectSound = value;
                 });
               },
-              activeThumbColor: Colors.blueAccent,
-              inactiveThumbColor: Colors.grey,
-              tileColor: const Color(0xFF1E1E1E),
+              activeThumbColor: Theme.of(context).colorScheme.primary,
+              inactiveThumbColor: Theme.of(
+                context,
+              ).colorScheme.onSurfaceVariant,
+              tileColor: Theme.of(context).colorScheme.surfaceContainer,
+              shape: RoundedRectangleBorder(
+                borderRadius: BorderRadius.circular(6),
+              ),
+            ),
+            const SizedBox(height: 12),
+            ListTile(
+              title: Text(
+                'Theme',
+                style: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurface,
+                ),
+              ),
+              trailing: DropdownButton<ThemeData>(
+                value: themeModel.currentTheme,
+                dropdownColor: Theme.of(context).colorScheme.surfaceContainer,
+                style: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurface,
+                ),
+                items: [
+                  DropdownMenuItem(
+                    value: Themes.dark,
+                    child: const Text('Dark'),
+                  ),
+                  DropdownMenuItem(
+                    value: Themes.light,
+                    child: const Text('Light'),
+                  ),
+                  DropdownMenuItem(
+                    value: Themes.nier,
+                    child: const Text('Nier'),
+                  ),
+                ],
+                onChanged: (theme) {
+                  if (theme != null) {
+                    themeModel.setTheme(theme);
+                  }
+                },
+              ),
+              tileColor: Theme.of(context).colorScheme.surfaceContainer,
               shape: RoundedRectangleBorder(
                 borderRadius: BorderRadius.circular(6),
               ),

lib/src/screens/start_screen.dart

@@ -28,8 +28,8 @@ class StartScreen extends StatelessWidget {
         decoration: BoxDecoration(
           gradient: LinearGradient(
             colors: [
-              const Color(0xFF121212),
-              Colors.grey[900]!,
+              Theme.of(context).colorScheme.surface,
+              Theme.of(context).colorScheme.surface,
             ],
             begin: Alignment.topLeft,
             end: Alignment.bottomRight,
@@ -113,14 +113,18 @@ class StartScreen extends StatelessWidget {
               const SizedBox(height: 16),
               Text(
                 title,
-                style: const TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
+                style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                  fontWeight: FontWeight.bold,
+                ),
                 textAlign: TextAlign.center,
               ),
               const SizedBox(height: 8),
               Expanded(
                 child: Text(
                   description,
-                  style: const TextStyle(fontSize: 12, color: Colors.grey),
+                  style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                    color: Theme.of(context).colorScheme.onSurfaceVariant,
+                  ),
                   textAlign: TextAlign.center,
                   softWrap: true,
                 ),

lib/src/screens/vocab_screen.dart

@@ -3,14 +3,28 @@ import 'dart:math';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import 'package:shared_preferences/shared_preferences.dart';
-import '../models/kanji_item.dart';
-import '../services/deck_repository.dart';
+import '../models/vocabulary_item.dart';
+import '../models/srs_item.dart';
+import 'package:hirameki_srs/src/services/vocab_deck_repository.dart';
 import '../services/distractor_generator.dart';
 import '../widgets/kanji_card.dart';
 import '../widgets/options_grid.dart';
 import 'package:audioplayers/audioplayers.dart';
 import 'settings_screen.dart';
 
+class _QuizState {
+  VocabularyItem? current;
+  List<String> options = [];
+  List<String> correctAnswers = [];
+  int score = 0;
+  int asked = 0;
+  Key key = UniqueKey();
+  String? selectedOption;
+  bool showResult = false;
+  List<VocabularyItem> shuffledDeck = [];
+  int currentIndex = 0;
+}
+
 class VocabScreen extends StatefulWidget {
   const VocabScreen({super.key});
 
@@ -18,19 +32,19 @@ class VocabScreen extends StatefulWidget {
   State<VocabScreen> createState() => _VocabScreenState();
 }
 
-class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStateMixin {
+class _VocabScreenState extends State<VocabScreen>
+    with SingleTickerProviderStateMixin {
   late TabController _tabController;
   List<VocabularyItem> _deck = [];
   bool _loading = false;
+  bool _isAnswering = false;
   String _status = 'Loading deck...';
   final DistractorGenerator _dg = DistractorGenerator();
   final _audioPlayer = AudioPlayer();
 
-  VocabularyItem? _current;
-  List<String> _options = [];
-  List<String> _correctAnswers = [];
-  int _score = 0;
-  int _asked = 0;
+  final _quizStates = [_QuizState(), _QuizState(), _QuizState()];
+  _QuizState get _currentQuizState => _quizStates[_tabController.index];
+
   bool _playAudio = true;
   bool _playCorrectSound = true;
   bool _apiKeyMissing = false;
@@ -41,7 +55,6 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
     _tabController = TabController(length: 3, vsync: this);
     _tabController.addListener(() {
       setState(() {});
-      _nextQuestion();
     });
     _loadSettings();
     _loadDeck();
@@ -68,7 +81,7 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
     });
 
     try {
-      final repo = Provider.of<DeckRepository>(context, listen: false);
+      final repo = Provider.of<VocabDeckRepository>(context, listen: false);
       await repo.loadApiKey();
       final apiKey = repo.apiKey;
 
@@ -96,7 +109,9 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
         _apiKeyMissing = false;
       });
 
-      _nextQuestion();
+      for (var i = 0; i < _tabController.length; i++) {
+        _nextQuestion(i);
+      }
     } catch (e) {
       setState(() {
         _status = 'Error: $e';
@@ -113,117 +128,141 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
         .join(' ');
   }
 
-  VocabQuizMode get _mode {
-    switch (_tabController.index) {
+  QuizMode _modeForIndex(int index) {
+    switch (index) {
       case 0:
-        return VocabQuizMode.vocabToEnglish;
+        return QuizMode.vocabToEnglish;
       case 1:
-        return VocabQuizMode.englishToVocab;
+        return QuizMode.englishToVocab;
       case 2:
-        return VocabQuizMode.audioToEnglish;
+        return QuizMode.audioToEnglish;
       default:
-        return VocabQuizMode.vocabToEnglish;
+        return QuizMode.vocabToEnglish;
     }
   }
 
-  void _nextQuestion() {
+  void _nextQuestion([int? index]) {
     if (_deck.isEmpty) return;
 
-    List<VocabularyItem> deck = _deck;
-    if (_mode == VocabQuizMode.audioToEnglish) {
-      deck = _deck.where((item) => item.pronunciationAudios.isNotEmpty).toList();
-      if (deck.isEmpty) {
+    final quizState = _quizStates[index ?? _tabController.index];
+    final mode = _modeForIndex(index ?? _tabController.index);
+
+    List<VocabularyItem> currentDeckForMode = _deck;
+    if (mode == QuizMode.audioToEnglish) {
+      currentDeckForMode = _deck
+          .where((item) => item.pronunciationAudios.isNotEmpty)
+          .toList();
+      if (currentDeckForMode.isEmpty) {
         setState(() {
           _status = 'No vocabulary with audio found.';
-          _current = null;
+          quizState.current = null;
         });
         return;
       }
     }
 
-    deck.sort((a, b) {
-      final aSrsItem = a.srsItems[_mode.toString()] ??
-          VocabSrsItem(vocabId: a.id, quizMode: _mode);
-      final bSrsItem = b.srsItems[_mode.toString()] ??
-          VocabSrsItem(vocabId: b.id, quizMode: _mode);
-
-      final stageComparison = aSrsItem.srsStage.compareTo(bSrsItem.srsStage);
-      if (stageComparison != 0) {
-        return stageComparison;
-      }
-      return aSrsItem.lastAsked.compareTo(bSrsItem.lastAsked);
-    });
-
-    _current = deck.first;
-    if (_mode == VocabQuizMode.audioToEnglish) {
-      _playCurrentAudio();
+    if (quizState.shuffledDeck.isEmpty ||
+        quizState.currentIndex >= quizState.shuffledDeck.length) {
+      quizState.shuffledDeck = currentDeckForMode.toList();
+      quizState.shuffledDeck.sort((a, b) {
+        final aSrsItem =
+            a.srsItems[mode.toString()] ??
+            SrsItem(subjectId: a.id, quizMode: mode);
+        final bSrsItem =
+            b.srsItems[mode.toString()] ??
+            SrsItem(subjectId: b.id, quizMode: mode);
+        final stageComparison = aSrsItem.srsStage.compareTo(bSrsItem.srsStage);
+        if (stageComparison != 0) {
+          return stageComparison;
+        }
+        return aSrsItem.lastAsked.compareTo(bSrsItem.lastAsked);
+      });
+      quizState.currentIndex = 0;
     }
 
-    _correctAnswers = [];
-    _options = [];
+    quizState.current = quizState.shuffledDeck[quizState.currentIndex];
+    quizState.currentIndex++;
 
-    switch (_mode) {
-      case VocabQuizMode.vocabToEnglish:
-      case VocabQuizMode.audioToEnglish:
-        _correctAnswers = [_current!.meanings.first];
-        _options = [
-          _correctAnswers.first,
-          ..._dg.generateVocabMeanings(_current!, _deck, 3)
-        ].map(_toTitleCase).toList()
-          ..shuffle();
+    quizState.key = UniqueKey();
+    quizState.correctAnswers = [];
+    quizState.options = [];
+    quizState.selectedOption = null;
+    quizState.showResult = false;
+
+    switch (mode) {
+      case QuizMode.vocabToEnglish:
+      case QuizMode.audioToEnglish:
+        quizState.correctAnswers = [quizState.current!.meanings.first];
+        quizState.options = [
+          quizState.correctAnswers.first,
+          ..._dg.generateVocabMeanings(quizState.current!, _deck, 3),
+        ].map(_toTitleCase).toList()..shuffle();
         break;
 
-      case VocabQuizMode.englishToVocab:
-        _correctAnswers = [_current!.characters];
-        _options = [
-          _correctAnswers.first,
-          ..._dg.generateVocab(_current!, _deck, 3)
+      case QuizMode.englishToVocab:
+        quizState.correctAnswers = [quizState.current!.characters];
+        quizState.options = [
+          quizState.correctAnswers.first,
+          ..._dg.generateVocab(quizState.current!, _deck, 3),
         ]..shuffle();
         break;
+      default:
+        break;
     }
 
-    setState(() {});
+    setState(() {
+      _isAnswering = false;
+    });
   }
 
-  Future<void> _playCurrentAudio() async {
-    if (_current == null || _current!.pronunciationAudios.isEmpty) return;
+  Future<void> _playCurrentAudio({bool playOnLoad = false}) async {
+    final current = _currentQuizState.current;
+    if (current == null || current.pronunciationAudios.isEmpty) return;
 
-    final maleAudios = _current!.pronunciationAudios.where((a) => a.gender == 'male');
-    final audioUrl = (maleAudios.isNotEmpty ? maleAudios.first.url : _current!.pronunciationAudios.first.url);
+    if (playOnLoad && !_playAudio) return;
+
+    final maleAudios = current.pronunciationAudios.where(
+      (a) => a.gender == 'male',
+    );
+    final audioUrl = (maleAudios.isNotEmpty
+        ? maleAudios.first.url
+        : current.pronunciationAudios.first.url);
 
     try {
       await _audioPlayer.play(UrlSource(audioUrl));
-    } catch (e) {
-      // Ignore player errors
-    }
+    } finally {}
   }
 
   void _answer(String option) async {
-    final isCorrect = _correctAnswers
+    final quizState = _currentQuizState;
+    final mode = _modeForIndex(_tabController.index);
+    final isCorrect = quizState.correctAnswers
         .map((a) => a.toLowerCase().trim())
         .contains(option.toLowerCase().trim());
 
-    final repo = Provider.of<DeckRepository>(context, listen: false);
-    final current = _current!;
+    final repo = Provider.of<VocabDeckRepository>(context, listen: false);
+    final current = quizState.current!;
 
-    final srsKey = _mode.toString();
+    final srsKey = mode.toString();
 
     var srsItemNullable = current.srsItems[srsKey];
     final isNew = srsItemNullable == null;
     final srsItem =
-        srsItemNullable ?? VocabSrsItem(vocabId: current.id, quizMode: _mode);
+        srsItemNullable ?? SrsItem(subjectId: current.id, quizMode: mode);
 
-    setState(() {
-      _asked += 1;
-      if (isCorrect) {
-        _score += 1;
-        srsItem.srsStage += 1;
-      } else {
-        srsItem.srsStage = max(0, srsItem.srsStage - 1);
-      }
-      srsItem.lastAsked = DateTime.now();
-      current.srsItems[srsKey] = srsItem;
-    });
+    quizState.asked += 1;
+    quizState.selectedOption = option;
+    quizState.showResult = true;
+    setState(() {});
+
+    if (isCorrect) {
+      quizState.score += 1;
+      srsItem.srsStage += 1;
+    } else {
+      srsItem.srsStage = max(0, srsItem.srsStage - 1);
+    }
+    srsItem.lastAsked = DateTime.now();
+    current.srsItems[srsKey] = srsItem;
 
     if (isNew) {
       await repo.insertVocabSrsItem(srsItem);
@@ -231,32 +270,34 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
       await repo.updateVocabSrsItem(srsItem);
     }
 
-    final correctDisplay = (_mode == VocabQuizMode.vocabToEnglish)
-        ? _toTitleCase(_correctAnswers.first)
-        : _correctAnswers.first;
+    final correctDisplay = (mode == QuizMode.vocabToEnglish)
+        ? _toTitleCase(quizState.correctAnswers.first)
+        : quizState.correctAnswers.first;
 
+    if (!mounted) return;
     final snack = SnackBar(
       content: Text(
         isCorrect ? 'Correct!' : 'Wrong — correct: $correctDisplay',
         style: TextStyle(
-          color: isCorrect ? Colors.greenAccent : Colors.redAccent,
+          color: isCorrect
+              ? Theme.of(context).colorScheme.tertiary
+              : Theme.of(context).colorScheme.error,
           fontWeight: FontWeight.bold,
         ),
       ),
-      backgroundColor: const Color(0xFF222222),
+      backgroundColor: Theme.of(context).colorScheme.surfaceContainerHighest,
       duration: const Duration(milliseconds: 900),
     );
-    if (mounted) {
-      ScaffoldMessenger.of(context).showSnackBar(snack);
-    }
+    ScaffoldMessenger.of(context).showSnackBar(snack);
 
     if (isCorrect) {
       if (_playCorrectSound) {
         await _audioPlayer.play(AssetSource('sfx/confirm.mp3'));
       }
-      if (_playAudio && _mode != VocabQuizMode.audioToEnglish) {
-        final maleAudios =
-            current.pronunciationAudios.where((a) => a.gender == 'male');
+      if (_playAudio) {
+        final maleAudios = current.pronunciationAudios.where(
+          (a) => a.gender == 'male',
+        );
         if (maleAudios.isNotEmpty) {
           final completer = Completer<void>();
           final sub = _audioPlayer.onPlayerComplete.listen((event) {
@@ -266,17 +307,17 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
           try {
             await _audioPlayer.play(UrlSource(maleAudios.first.url));
             await completer.future.timeout(const Duration(seconds: 5));
-          } catch (e) {
-            // Ignore player errors
           } finally {
             await sub.cancel();
           }
         }
       }
-    } else {
-      await Future.delayed(const Duration(milliseconds: 900));
     }
 
+    setState(() {
+      _isAnswering = true;
+    });
+
     _nextQuestion();
   }
 
@@ -289,13 +330,19 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
           child: Column(
             mainAxisAlignment: MainAxisAlignment.center,
             children: [
-              const Text('WaniKani API key is not set.', style: TextStyle(color: Colors.white)),
+              Text(
+                'WaniKani API key is not set.',
+                style: TextStyle(
+                  color: Theme.of(context).colorScheme.onSurface,
+                ),
+              ),
               const SizedBox(height: 16),
               ElevatedButton(
                 onPressed: () async {
                   await Navigator.of(context).push(
                     MaterialPageRoute(builder: (_) => const SettingsScreen()),
                   );
+                  if (!mounted) return;
                   _loadDeck();
                 },
                 child: const Text('Go to Settings'),
@@ -306,31 +353,6 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
       );
     }
 
-    Widget promptWidget;
-
-    if (_current == null) {
-      promptWidget = const SizedBox.shrink();
-    } else if (_mode == VocabQuizMode.audioToEnglish) {
-      promptWidget = IconButton(
-        icon: const Icon(Icons.volume_up, color: Colors.white, size: 64),
-        onPressed: _playCurrentAudio,
-      );
-    } else {
-      String promptText = '';
-      switch (_mode) {
-        case VocabQuizMode.vocabToEnglish:
-          promptText = _current?.characters ?? '';
-          break;
-        case VocabQuizMode.englishToVocab:
-          promptText = _current != null ? _toTitleCase(_current!.meanings.first) : '';
-          break;
-        case VocabQuizMode.audioToEnglish:
-          // Handled above
-          break;
-      }
-      promptWidget = Text(promptText, style: const TextStyle(fontSize: 48, color: Colors.white));
-    }
-
     return Scaffold(
       appBar: AppBar(
         title: const Text('Vocabulary Quiz'),
@@ -343,64 +365,113 @@ class _VocabScreenState extends State<VocabScreen> with SingleTickerProviderStat
           ],
         ),
       ),
-      backgroundColor: const Color(0xFF121212),
-      body: Padding(
-        padding: const EdgeInsets.all(16.0),
-        child: Column(
-          children: [
-            Row(
-              children: [
-                Expanded(
-                  child: Text(
-                    _status,
-                    style: const TextStyle(color: Colors.white),
-                  ),
-                ),
-                if (_loading)
-                  const CircularProgressIndicator(color: Colors.blueAccent),
-              ],
-            ),
-            const SizedBox(height: 18),
-            Expanded(
-              flex: 3,
-              child: Center(
-                child: ConstrainedBox(
-                  constraints: const BoxConstraints(
-                    minWidth: 0,
-                    maxWidth: 500,
-                    minHeight: 150,
-                  ),
-                  child: KanjiCard(
-                    characterWidget: promptWidget,
-                    subtitle: '',
-                    backgroundColor: const Color(0xFF1E1E1E),
-                    textColor: Colors.white,
-                  ),
-                ),
-              ),
-            ),
-            const SizedBox(height: 12),
-            SafeArea(
-              top: false,
-              child: Column(
-                children: [
-                  OptionsGrid(
-                    options: _options,
-                    onSelected: _answer,
-                    buttonColor: const Color(0xFF1E1E1E),
-                    textColor: Colors.white,
-                  ),
-                  const SizedBox(height: 8),
-                  Text(
-                    'Score: $_score / $_asked',
-                    style: const TextStyle(color: Colors.white),
-                  ),
-                ],
-              ),
-            ),
-          ],
-        ),
+      body: TabBarView(
+        controller: _tabController,
+        children: [_buildQuizPage(0), _buildQuizPage(1), _buildQuizPage(2)],
       ),
     );
   }
-}
+
+  Widget _buildQuizPage(int index) {
+    final quizState = _quizStates[index];
+    final mode = _modeForIndex(index);
+
+    Widget promptWidget;
+
+    if (quizState.current == null) {
+      promptWidget = const SizedBox.shrink();
+    } else if (mode == QuizMode.audioToEnglish) {
+      promptWidget = IconButton(
+        icon: Icon(
+          Icons.volume_up,
+          color: Theme.of(context).colorScheme.onSurface,
+          size: 64,
+        ),
+        onPressed: _playCurrentAudio,
+      );
+    } else {
+      String promptText = '';
+      switch (mode) {
+        case QuizMode.vocabToEnglish:
+          promptText = quizState.current!.characters;
+          break;
+        case QuizMode.englishToVocab:
+          promptText = _toTitleCase(quizState.current!.meanings.first);
+          break;
+        case QuizMode.audioToEnglish:
+          break;
+        default:
+          break;
+      }
+      promptWidget = Text(
+        promptText,
+        style: TextStyle(
+          fontSize: 48,
+          color: Theme.of(context).colorScheme.onSurface,
+        ),
+      );
+    }
+
+    return Padding(
+      key: quizState.key,
+      padding: const EdgeInsets.all(16.0),
+      child: Column(
+        children: [
+          Row(
+            children: [
+              Expanded(
+                child: Text(
+                  _status,
+                  style: TextStyle(
+                    color: Theme.of(context).colorScheme.onSurface,
+                  ),
+                ),
+              ),
+              if (_loading)
+                CircularProgressIndicator(
+                  color: Theme.of(context).colorScheme.primary,
+                ),
+            ],
+          ),
+          const SizedBox(height: 18),
+          Expanded(
+            flex: 3,
+            child: Center(
+              child: ConstrainedBox(
+                constraints: const BoxConstraints(
+                  minWidth: 0,
+                  maxWidth: 500,
+                  minHeight: 150,
+                ),
+                child: KanjiCard(characterWidget: promptWidget, subtitle: ''),
+              ),
+            ),
+          ),
+          const SizedBox(height: 12),
+          SafeArea(
+            top: false,
+            child: Column(
+              children: [
+                OptionsGrid(
+                  options: quizState.options,
+                  onSelected: _isAnswering ? (option) {} : _answer,
+                  isDisabled: false,
+                  selectedOption: null,
+                  correctAnswers: [],
+                  showResult: false,
+                ),
+                const SizedBox(height: 8),
+                Text(
+                  'Score: ${quizState.score} / ${quizState.asked}',
+                  style: TextStyle(
+                    color: Theme.of(context).colorScheme.onSurface,
+                  ),
+                ),
+              ],
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/src/services/custom_deck_repository.dart

@@ -23,12 +23,7 @@ class CustomDeckRepository {
   }
 
   Future<void> updateCard(CustomKanjiItem item) async {
-    final deck = await getCustomDeck();
-    final index = deck.indexWhere((element) => element.characters == item.characters);
-    if (index != -1) {
-      deck[index] = item;
-      await saveDeck(deck);
-    }
+    await updateCards([item]);
   }
 
   Future<void> updateCards(List<CustomKanjiItem> itemsToUpdate) async {

lib/src/services/database_constants.dart

@@ -0,0 +1,27 @@
+
+class DbConstants {
+  static const String settingsTable = 'settings';
+  static const String kanjiTable = 'kanji';
+  static const String srsItemsTable = 'srs_items';
+  static const String vocabularyTable = 'vocabulary';
+  static const String srsVocabItemsTable = 'srs_vocab_items';
+
+  static const String keyColumn = 'key';
+  static const String valueColumn = 'value';
+
+  static const String idColumn = 'id';
+  static const String levelColumn = 'level';
+  static const String charactersColumn = 'characters';
+  static const String meaningsColumn = 'meanings';
+  static const String onyomiColumn = 'onyomi';
+  static const String kunyomiColumn = 'kunyomi';
+  static const String readingsColumn = 'readings';
+  static const String pronunciationAudiosColumn = 'pronunciation_audios';
+
+  static const String kanjiIdColumn = 'kanjiId';
+  static const String vocabIdColumn = 'vocabId';
+  static const String quizModeColumn = 'quizMode';
+  static const String readingTypeColumn = 'readingType';
+  static const String srsStageColumn = 'srsStage';
+  static const String lastAskedColumn = 'lastAsked';
+}

lib/src/services/database_helper.dart

@@ -0,0 +1,92 @@
+import 'package:path/path.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:sqflite/sqflite.dart';
+import 'database_constants.dart';
+
+class DatabaseHelper {
+  static final DatabaseHelper _instance = DatabaseHelper._internal();
+  static Database? _db;
+
+  factory DatabaseHelper() {
+    return _instance;
+  }
+
+  DatabaseHelper._internal();
+
+  Future<Database> get db async {
+    if (_db != null) return _db!;
+    _db = await _openDb();
+    return _db!;
+  }
+
+  Future<void> close() async {
+    if (_db != null) {
+      await _db!.close();
+      _db = null;
+    }
+  }
+
+  Future<Database> _openDb() async {
+    final dir = await getApplicationDocumentsDirectory();
+    final path = join(dir.path, 'wanikani_srs.db');
+
+    return openDatabase(
+      path,
+      version: 7,
+      onCreate: (db, version) async {
+        await db.execute(
+          '''CREATE TABLE ${DbConstants.kanjiTable} (${DbConstants.idColumn} INTEGER PRIMARY KEY, ${DbConstants.levelColumn} INTEGER, ${DbConstants.charactersColumn} TEXT, ${DbConstants.meaningsColumn} TEXT, ${DbConstants.onyomiColumn} TEXT, ${DbConstants.kunyomiColumn} TEXT)''',
+        );
+        await db.execute(
+          '''CREATE TABLE ${DbConstants.settingsTable} (${DbConstants.keyColumn} TEXT PRIMARY KEY, ${DbConstants.valueColumn} TEXT)''',
+        );
+        await db.execute(
+          '''CREATE TABLE ${DbConstants.srsItemsTable} (${DbConstants.kanjiIdColumn} INTEGER, ${DbConstants.quizModeColumn} TEXT, ${DbConstants.readingTypeColumn} TEXT, ${DbConstants.srsStageColumn} INTEGER, ${DbConstants.lastAskedColumn} TEXT, PRIMARY KEY (${DbConstants.kanjiIdColumn}, ${DbConstants.quizModeColumn}, ${DbConstants.readingTypeColumn}))''',
+        );
+        await db.execute(
+          '''CREATE TABLE ${DbConstants.vocabularyTable} (${DbConstants.idColumn} INTEGER PRIMARY KEY, ${DbConstants.levelColumn} INTEGER, ${DbConstants.charactersColumn} TEXT, ${DbConstants.meaningsColumn} TEXT, ${DbConstants.readingsColumn} TEXT, ${DbConstants.pronunciationAudiosColumn} TEXT)''',
+        );
+        await db.execute(
+          '''CREATE TABLE ${DbConstants.srsVocabItemsTable} (${DbConstants.vocabIdColumn} INTEGER, ${DbConstants.quizModeColumn} TEXT, ${DbConstants.srsStageColumn} INTEGER, ${DbConstants.lastAskedColumn} TEXT, PRIMARY KEY (${DbConstants.vocabIdColumn}, ${DbConstants.quizModeColumn}))''',
+        );
+      },
+      onUpgrade: (db, oldVersion, newVersion) async {
+        if (oldVersion < 2) {
+          await db.execute(
+            '''CREATE TABLE IF NOT EXISTS ${DbConstants.settingsTable} (${DbConstants.keyColumn} TEXT PRIMARY KEY, ${DbConstants.valueColumn} TEXT)''',
+          );
+        }
+        if (oldVersion < 4) {
+          await db.execute(
+            '''CREATE TABLE IF NOT EXISTS ${DbConstants.srsItemsTable} (${DbConstants.kanjiIdColumn} INTEGER, ${DbConstants.quizModeColumn} TEXT, ${DbConstants.readingTypeColumn} TEXT, ${DbConstants.srsStageColumn} INTEGER, ${DbConstants.lastAskedColumn} TEXT, PRIMARY KEY (${DbConstants.kanjiIdColumn}, ${DbConstants.quizModeColumn}, ${DbConstants.readingTypeColumn}))''',
+          );
+        }
+        if (oldVersion < 5) {
+          await db.execute(
+            '''CREATE TABLE IF NOT EXISTS ${DbConstants.vocabularyTable} (${DbConstants.idColumn} INTEGER PRIMARY KEY, ${DbConstants.charactersColumn} TEXT, ${DbConstants.meaningsColumn} TEXT, ${DbConstants.readingsColumn} TEXT)''',
+          );
+          await db.execute(
+            '''CREATE TABLE IF NOT EXISTS ${DbConstants.srsVocabItemsTable} (${DbConstants.vocabIdColumn} INTEGER, ${DbConstants.quizModeColumn} TEXT, ${DbConstants.srsStageColumn} INTEGER, ${DbConstants.lastAskedColumn} TEXT, PRIMARY KEY (${DbConstants.vocabIdColumn}, ${DbConstants.quizModeColumn}))''',
+          );
+        }
+        if (oldVersion < 6) {
+          try {
+            await db.execute(
+              'ALTER TABLE ${DbConstants.vocabularyTable} ADD COLUMN ${DbConstants.pronunciationAudiosColumn} TEXT',
+            );
+          } catch (_) {
+            // Ignore error, column might already exist
+          }
+        }
+        if (oldVersion < 7) {
+          try {
+            await db.execute('ALTER TABLE ${DbConstants.kanjiTable} ADD COLUMN ${DbConstants.levelColumn} INTEGER');
+            await db.execute('ALTER TABLE ${DbConstants.vocabularyTable} ADD COLUMN ${DbConstants.levelColumn} INTEGER');
+          } catch (_) {
+            // Ignore error, column might already exist
+          }
+        }
+      },
+    );
+  }
+}

lib/src/services/deck_repository.dart

@@ -1,15 +1,14 @@
 import 'dart:async';
-import 'dart:convert';
-import 'package:path/path.dart';
-import 'package:path_provider/path_provider.dart';
 import 'package:sqflite/sqflite.dart';
 import '../models/kanji_item.dart';
+import '../models/srs_item.dart';
 import '../api/wk_client.dart';
+import 'database_constants.dart';
+import 'database_helper.dart';
 
 import 'package:flutter_dotenv/flutter_dotenv.dart';
 
 class DeckRepository {
-  Database? _db;
   String? _apiKey;
 
   Future<void> setApiKey(String apiKey) async {
@@ -19,140 +18,75 @@ class DeckRepository {
 
   String? get apiKey => _apiKey;
 
-  Future<Database> _openDb() async {
-    if (_db != null) return _db!;
-    final dir = await getApplicationDocumentsDirectory();
-    final path = join(dir.path, 'wanikani_srs.db');
-
-    _db = await openDatabase(
-      path,
-      version: 7,
-      onCreate: (db, version) async {
-        await db.execute(
-          '''CREATE TABLE kanji (id INTEGER PRIMARY KEY, level INTEGER, characters TEXT, meanings TEXT, onyomi TEXT, kunyomi TEXT)''',
-        );
-        await db.execute(
-          '''CREATE TABLE settings (key TEXT PRIMARY KEY, value TEXT)''',
-        );
-        await db.execute(
-          '''CREATE TABLE srs_items (kanjiId INTEGER, quizMode TEXT, readingType TEXT, srsStage INTEGER, lastAsked TEXT, PRIMARY KEY (kanjiId, quizMode, readingType))''',
-        );
-        await db.execute(
-          '''CREATE TABLE vocabulary (id INTEGER PRIMARY KEY, level INTEGER, characters TEXT, meanings TEXT, readings TEXT, pronunciation_audios TEXT)''',
-        );
-        await db.execute(
-          '''CREATE TABLE srs_vocab_items (vocabId INTEGER, quizMode TEXT, srsStage INTEGER, lastAsked TEXT, PRIMARY KEY (vocabId, quizMode))''',
-        );
-      },
-      onUpgrade: (db, oldVersion, newVersion) async {
-        if (oldVersion < 2) {
-          await db.execute(
-            '''CREATE TABLE IF NOT EXISTS settings (key TEXT PRIMARY KEY, value TEXT)''',
-          );
-        }
-        if (oldVersion < 3) {
-          // Migration from version 2 to 3 was flawed, so we just drop the columns if they exist
-        }
-        if (oldVersion < 4) {
-          await db.execute(
-            '''CREATE TABLE srs_items (kanjiId INTEGER, quizMode TEXT, readingType TEXT, srsStage INTEGER, lastAsked TEXT, PRIMARY KEY (kanjiId, quizMode, readingType))''',
-          );
-          // We are not migrating the old srs data, as it was not mode-specific.
-          // Old columns will be dropped.
-        }
-        if (oldVersion < 5) {
-          await db.execute(
-            '''CREATE TABLE vocabulary (id INTEGER PRIMARY KEY, characters TEXT, meanings TEXT, readings TEXT)''',
-          );
-          await db.execute(
-            '''CREATE TABLE srs_vocab_items (vocabId INTEGER, quizMode TEXT, srsStage INTEGER, lastAsked TEXT, PRIMARY KEY (vocabId, quizMode))''',
-          );
-        }
-        if (oldVersion < 6) {
-          try {
-            await db.execute(
-              'ALTER TABLE vocabulary ADD COLUMN pronunciation_audios TEXT',
-            );
-          } catch (_) {
-            // Ignore error, column might already exist
-          }
-        }
-        if (oldVersion < 7) {
-          try {
-            await db.execute('ALTER TABLE kanji ADD COLUMN level INTEGER');
-            await db.execute('ALTER TABLE vocabulary ADD COLUMN level INTEGER');
-          } catch (_) {
-            // Ignore error, column might already exist
-          }
-        }
-      },
-    );
-
-    return _db!;
-  }
-
   Future<void> saveApiKey(String apiKey) async {
-    final db = await _openDb();
-    await db.insert('settings', {
-      'key': 'apiKey',
-      'value': apiKey,
+    final db = await DatabaseHelper().db;
+    await db.insert(DbConstants.settingsTable, {
+      DbConstants.keyColumn: 'apiKey',
+      DbConstants.valueColumn: apiKey,
     }, conflictAlgorithm: ConflictAlgorithm.replace);
   }
 
   Future<String?> loadApiKey() async {
-    final envApiKey = dotenv.env['WANIKANI_API_KEY'];
-    if (envApiKey != null && envApiKey.isNotEmpty) {
-      _apiKey = envApiKey;
+    final db = await DatabaseHelper().db;
+    final rows = await db.query(
+      DbConstants.settingsTable,
+      where: '${DbConstants.keyColumn} = ?',
+      whereArgs: ['apiKey'],
+    );
+
+    if (rows.isNotEmpty) {
+      _apiKey = rows.first[DbConstants.valueColumn] as String;
       return _apiKey;
     }
 
-    final db = await _openDb();
-    final rows = await db.query(
-      'settings',
-      where: 'key = ?',
-      whereArgs: ['apiKey'],
-    );
-    if (rows.isNotEmpty) {
-      _apiKey = rows.first['value'] as String;
-      return _apiKey;
+    try {
+      final envApiKey = dotenv.env['WANIKANI_API_KEY'];
+      if (envApiKey != null && envApiKey.isNotEmpty) {
+        await saveApiKey(envApiKey);
+        _apiKey = envApiKey;
+        return _apiKey;
+      }
+    } catch (e) {
+      // dotenv is not initialized
     }
+
     return null;
   }
 
   Future<void> saveKanji(List<KanjiItem> items) async {
-    final db = await _openDb();
+    final db = await DatabaseHelper().db;
     final batch = db.batch();
     for (final it in items) {
-      batch.insert('kanji', {
-        'id': it.id,
-        'level': it.level,
-        'characters': it.characters,
-        'meanings': it.meanings.join('|'),
-        'onyomi': it.onyomi.join('|'),
-        'kunyomi': it.kunyomi.join('|'),
+      batch.insert(DbConstants.kanjiTable, {
+        DbConstants.idColumn: it.id,
+        DbConstants.levelColumn: it.level,
+        DbConstants.charactersColumn: it.characters,
+        DbConstants.meaningsColumn: it.meanings.join('|'),
+        DbConstants.onyomiColumn: it.onyomi.join('|'),
+        DbConstants.kunyomiColumn: it.kunyomi.join('|'),
       }, conflictAlgorithm: ConflictAlgorithm.replace);
     }
     await batch.commit(noResult: true);
   }
 
   Future<List<KanjiItem>> loadKanji() async {
-    final db = await _openDb();
-    final rows = await db.query('kanji');
+    final db = await DatabaseHelper().db;
+    final rows = await db.query(DbConstants.kanjiTable);
     final kanjiItems = rows
         .map(
           (r) => KanjiItem(
-            id: r['id'] as int,
-            level: r['level'] as int? ?? 0,
-            characters: r['characters'] as String,
-            meanings: (r['meanings'] as String)
+            id: r[DbConstants.idColumn] as int,
+            level: r[DbConstants.levelColumn] as int? ?? 0,
+            characters: r[DbConstants.charactersColumn] as String,
+            meanings: (r[DbConstants.meaningsColumn] as String)
                 .split('|')
                 .where((s) => s.isNotEmpty)
                 .toList(),
-            onyomi: (r['onyomi'] as String)
+            onyomi: (r[DbConstants.onyomiColumn] as String)
                 .split('|')
                 .where((s) => s.isNotEmpty)
                 .toList(),
-            kunyomi: (r['kunyomi'] as String)
+            kunyomi: (r[DbConstants.kunyomiColumn] as String)
                 .split('|')
                 .where((s) => s.isNotEmpty)
                 .toList(),
@@ -160,8 +94,23 @@ class DeckRepository {
         )
         .toList();
 
+    final srsRows = await db.query(DbConstants.srsItemsTable);
+    final srsItemsByKanjiId = <int, List<SrsItem>>{};
+    for (final r in srsRows) {
+      final srsItem = SrsItem(
+        subjectId: r[DbConstants.kanjiIdColumn] as int,
+        quizMode: QuizMode.values.firstWhere(
+          (e) => e.toString() == r[DbConstants.quizModeColumn] as String,
+        ),
+        readingType: r[DbConstants.readingTypeColumn] as String?,
+        srsStage: r[DbConstants.srsStageColumn] as int,
+        lastAsked: DateTime.parse(r[DbConstants.lastAskedColumn] as String),
+      );
+      srsItemsByKanjiId.putIfAbsent(srsItem.subjectId, () => []).add(srsItem);
+    }
+
     for (final item in kanjiItems) {
-      final srsItems = await getSrsItems(item.id);
+      final srsItems = srsItemsByKanjiId[item.id] ?? [];
       for (final srsItem in srsItems) {
         final key = srsItem.quizMode.toString() + (srsItem.readingType ?? '');
         item.srsItems[key] = srsItem;
@@ -171,47 +120,27 @@ class DeckRepository {
     return kanjiItems;
   }
 
-  Future<List<SrsItem>> getSrsItems(int kanjiId) async {
-    final db = await _openDb();
-    final rows = await db.query(
-      'srs_items',
-      where: 'kanjiId = ?',
-      whereArgs: [kanjiId],
-    );
-    return rows.map((r) {
-      return SrsItem(
-        kanjiId: r['kanjiId'] as int,
-        quizMode: QuizMode.values.firstWhere(
-          (e) => e.toString() == r['quizMode'] as String,
-        ),
-        readingType: r['readingType'] as String?,
-        srsStage: r['srsStage'] as int,
-        lastAsked: DateTime.parse(r['lastAsked'] as String),
-      );
-    }).toList();
-  }
-
   Future<void> updateSrsItem(SrsItem item) async {
-    final db = await _openDb();
+    final db = await DatabaseHelper().db;
     await db.update(
-      'srs_items',
+      DbConstants.srsItemsTable,
       {
-        'srsStage': item.srsStage,
-        'lastAsked': item.lastAsked.toIso8601String(),
+        DbConstants.srsStageColumn: item.srsStage,
+        DbConstants.lastAskedColumn: item.lastAsked.toIso8601String(),
       },
-      where: 'kanjiId = ? AND quizMode = ? AND readingType = ?',
-      whereArgs: [item.kanjiId, item.quizMode.toString(), item.readingType],
+      where: '${DbConstants.kanjiIdColumn} = ? AND ${DbConstants.quizModeColumn} = ? AND ${DbConstants.readingTypeColumn} = ?',
+      whereArgs: [item.subjectId, item.quizMode.toString(), item.readingType],
     );
   }
 
   Future<void> insertSrsItem(SrsItem item) async {
-    final db = await _openDb();
-    await db.insert('srs_items', {
-      'kanjiId': item.kanjiId,
-      'quizMode': item.quizMode.toString(),
-      'readingType': item.readingType,
-      'srsStage': item.srsStage,
-      'lastAsked': item.lastAsked.toIso8601String(),
+    final db = await DatabaseHelper().db;
+    await db.insert(DbConstants.srsItemsTable, {
+      DbConstants.kanjiIdColumn: item.subjectId,
+      DbConstants.quizModeColumn: item.quizMode.toString(),
+      DbConstants.readingTypeColumn: item.readingType,
+      DbConstants.srsStageColumn: item.srsStage,
+      DbConstants.lastAskedColumn: item.lastAsked.toIso8601String(),
     }, conflictAlgorithm: ConflictAlgorithm.replace);
   }
 
@@ -254,155 +183,4 @@ class DeckRepository {
     await saveKanji(items);
     return items;
   }
-
-  Future<List<VocabSrsItem>> getVocabSrsItems(int vocabId) async {
-    final db = await _openDb();
-    final rows = await db.query(
-      'srs_vocab_items',
-      where: 'vocabId = ?',
-      whereArgs: [vocabId],
-    );
-    return rows.map((r) {
-      return VocabSrsItem(
-        vocabId: r['vocabId'] as int,
-        quizMode: VocabQuizMode.values.firstWhere(
-          (e) => e.toString() == r['quizMode'] as String,
-        ),
-        srsStage: r['srsStage'] as int,
-        lastAsked: DateTime.parse(r['lastAsked'] as String),
-      );
-    }).toList();
-  }
-
-  Future<void> updateVocabSrsItem(VocabSrsItem item) async {
-    final db = await _openDb();
-    await db.update(
-      'srs_vocab_items',
-      {
-        'srsStage': item.srsStage,
-        'lastAsked': item.lastAsked.toIso8601String(),
-      },
-      where: 'vocabId = ? AND quizMode = ?',
-      whereArgs: [item.vocabId, item.quizMode.toString()],
-    );
-  }
-
-  Future<void> insertVocabSrsItem(VocabSrsItem item) async {
-    final db = await _openDb();
-    await db.insert('srs_vocab_items', {
-      'vocabId': item.vocabId,
-      'quizMode': item.quizMode.toString(),
-      'srsStage': item.srsStage,
-      'lastAsked': item.lastAsked.toIso8601String(),
-    }, conflictAlgorithm: ConflictAlgorithm.replace);
-  }
-
-  Future<void> saveVocabulary(List<VocabularyItem> items) async {
-    final db = await _openDb();
-    final batch = db.batch();
-    for (final it in items) {
-      final audios = it.pronunciationAudios
-          .map((a) => {'url': a.url, 'gender': a.gender})
-          .toList();
-      batch.insert('vocabulary', {
-        'id': it.id,
-        'level': it.level,
-        'characters': it.characters,
-        'meanings': it.meanings.join('|'),
-        'readings': it.readings.join('|'),
-        'pronunciation_audios': jsonEncode(audios),
-      }, conflictAlgorithm: ConflictAlgorithm.replace);
-    }
-    await batch.commit(noResult: true);
-  }
-
-  Future<List<VocabularyItem>> loadVocabulary() async {
-    final db = await _openDb();
-    final rows = await db.query('vocabulary');
-    final vocabItems = rows.map((r) {
-      final audiosRaw = r['pronunciation_audios'] as String?;
-      final List<PronunciationAudio> audios = [];
-      if (audiosRaw != null && audiosRaw.isNotEmpty) {
-        try {
-          final decoded = jsonDecode(audiosRaw) as List;
-          for (final audioData in decoded) {
-            audios.add(
-              PronunciationAudio(
-                url: audioData['url'] as String,
-                gender: audioData['gender'] as String,
-              ),
-            );
-          }
-        } catch (e) {
-          // Error decoding, so we'll just have no audio for this item
-        }
-      }
-      return VocabularyItem(
-        id: r['id'] as int,
-        level: r['level'] as int? ?? 0,
-        characters: r['characters'] as String,
-        meanings: (r['meanings'] as String)
-            .split('|')
-            .where((s) => s.isNotEmpty)
-            .toList(),
-        readings: (r['readings'] as String)
-            .split('|')
-            .where((s) => s.isNotEmpty)
-            .toList(),
-        pronunciationAudios: audios,
-      );
-    }).toList();
-
-    for (final item in vocabItems) {
-      final srsItems = await getVocabSrsItems(item.id);
-      for (final srsItem in srsItems) {
-        final key = srsItem.quizMode.toString();
-        item.srsItems[key] = srsItem;
-      }
-    }
-
-    return vocabItems;
-  }
-
-  Future<List<VocabularyItem>> fetchAndCacheVocabularyFromWk([
-    String? apiKey,
-  ]) async {
-    final key = apiKey ?? _apiKey;
-    if (key == null) throw Exception('API key not set');
-
-    final client = WkClient(key);
-    final assignments = await client.fetchAllAssignments(
-      subjectTypes: ['vocabulary'],
-    );
-
-    final unlocked = <int>{};
-    for (final a in assignments) {
-      final data = a['data'] as Map<String, dynamic>;
-      final sidRaw = data['subject_id'];
-      if (sidRaw == null) continue;
-      final sid = sidRaw is int ? sidRaw : int.tryParse(sidRaw.toString());
-      if (sid == null) continue;
-      final started = data['started_at'];
-      final srs = data['srs_stage'];
-      final isUnlocked = (started != null) || (srs != null && (srs as int) > 0);
-      if (isUnlocked) unlocked.add(sid);
-    }
-
-    if (unlocked.isEmpty) return [];
-
-    final subjects = await client.fetchSubjectsByIds(unlocked.toList());
-    final items = subjects
-        .where(
-          (s) =>
-              s['object'] == 'vocabulary' ||
-              (s['data'] != null &&
-                  (s['data'] as Map)['object_type'] == 'vocabulary'),
-        )
-        .map((s) => VocabularyItem.fromSubject(s))
-        .where((k) => k.characters.isNotEmpty && k.meanings.isNotEmpty)
-        .toList();
-
-    await saveVocabulary(items);
-    return items;
-  }
 }

lib/src/services/distractor_generator.dart

@@ -1,4 +1,5 @@
 import '../models/kanji_item.dart';
+import '../models/vocabulary_item.dart';
 import 'dart:math';
 
 class DistractorGenerator {

lib/src/services/vocab_deck_repository.dart

@@ -0,0 +1,204 @@
+import 'dart:async';
+import 'dart:convert';
+import 'package:sqflite/sqflite.dart';
+import '../models/vocabulary_item.dart';
+import '../models/srs_item.dart';
+import '../api/wk_client.dart';
+import 'database_helper.dart';
+
+import 'package:flutter_dotenv/flutter_dotenv.dart';
+
+class VocabDeckRepository {
+  String? _apiKey;
+
+  Future<void> setApiKey(String apiKey) async {
+    _apiKey = apiKey;
+    await saveApiKey(apiKey);
+  }
+
+  String? get apiKey => _apiKey;
+
+  Future<void> saveApiKey(String apiKey) async {
+    final db = await DatabaseHelper().db;
+    await db.insert('settings', {
+      'key': 'apiKey',
+      'value': apiKey,
+    }, conflictAlgorithm: ConflictAlgorithm.replace);
+  }
+
+
+  Future<String?> loadApiKey() async {
+    String? envApiKey;
+    try {
+      envApiKey = dotenv.env['WANIKANI_API_KEY'];
+    } catch (e) {
+      envApiKey = null;
+    }
+
+    if (envApiKey != null && envApiKey.isNotEmpty) {
+      _apiKey = envApiKey;
+      return _apiKey;
+    }
+
+    final db = await DatabaseHelper().db;
+    final rows = await db.query(
+      'settings',
+      where: 'key = ?',
+      whereArgs: ['apiKey'],
+    );
+    if (rows.isNotEmpty) {
+      _apiKey = rows.first['value'] as String;
+      return _apiKey;
+    }
+    return null;
+  }
+
+  Future<List<SrsItem>> getVocabSrsItems(int vocabId) async {
+    final db = await DatabaseHelper().db;
+    final rows = await db.query(
+      'srs_vocab_items',
+      where: 'vocabId = ?',
+      whereArgs: [vocabId],
+    );
+    return rows.map((r) {
+      return SrsItem(
+        subjectId: r['vocabId'] as int,
+        quizMode: QuizMode.values.firstWhere(
+          (e) => e.toString() == r['quizMode'] as String,
+        ),
+        srsStage: r['srsStage'] as int,
+        lastAsked: DateTime.parse(r['lastAsked'] as String),
+      );
+    }).toList();
+  }
+
+  Future<void> updateVocabSrsItem(SrsItem item) async {
+    final db = await DatabaseHelper().db;
+    await db.update(
+      'srs_vocab_items',
+      {
+        'srsStage': item.srsStage,
+        'lastAsked': item.lastAsked.toIso8601String(),
+      },
+      where: 'vocabId = ? AND quizMode = ?',
+      whereArgs: [item.subjectId, item.quizMode.toString()],
+    );
+  }
+
+  Future<void> insertVocabSrsItem(SrsItem item) async {
+    final db = await DatabaseHelper().db;
+    await db.insert('srs_vocab_items', {
+      'vocabId': item.subjectId,
+      'quizMode': item.quizMode.toString(),
+      'srsStage': item.srsStage,
+      'lastAsked': item.lastAsked.toIso8601String(),
+    }, conflictAlgorithm: ConflictAlgorithm.replace);
+  }
+
+  Future<void> saveVocabulary(List<VocabularyItem> items) async {
+    final db = await DatabaseHelper().db;
+    final batch = db.batch();
+    for (final it in items) {
+      final audios = it.pronunciationAudios
+          .map((a) => {'url': a.url, 'gender': a.gender})
+          .toList();
+      batch.insert('vocabulary', {
+        'id': it.id,
+        'level': it.level,
+        'characters': it.characters,
+        'meanings': it.meanings.join('|'),
+        'readings': it.readings.join('|'),
+        'pronunciation_audios': jsonEncode(audios),
+      }, conflictAlgorithm: ConflictAlgorithm.replace);
+    }
+    await batch.commit(noResult: true);
+  }
+
+  Future<List<VocabularyItem>> loadVocabulary() async {
+    final db = await DatabaseHelper().db;
+    final rows = await db.query('vocabulary');
+    final vocabItems = rows.map((r) {
+      final audiosRaw = r['pronunciation_audios'] as String?;
+      final List<PronunciationAudio> audios = [];
+      if (audiosRaw != null && audiosRaw.isNotEmpty) {
+        try {
+          final decoded = jsonDecode(audiosRaw) as List;
+          for (final audioData in decoded) {
+            audios.add(
+              PronunciationAudio(
+                url: audioData['url'] as String,
+                gender: audioData['gender'] as String,
+              ),
+            );
+          }
+        } finally {}
+      }
+      return VocabularyItem(
+        id: r['id'] as int,
+        level: r['level'] as int? ?? 0,
+        characters: r['characters'] as String,
+        meanings: (r['meanings'] as String)
+            .split('|')
+            .where((s) => s.isNotEmpty)
+            .toList(),
+        readings: (r['readings'] as String)
+            .split('|')
+            .where((s) => s.isNotEmpty)
+            .toList(),
+        pronunciationAudios: audios,
+      );
+    }).toList();
+
+    for (final item in vocabItems) {
+      final srsItems = await getVocabSrsItems(item.id);
+      for (final srsItem in srsItems) {
+        final key = srsItem.quizMode.toString();
+        item.srsItems[key] = srsItem;
+      }
+    }
+
+    return vocabItems;
+  }
+
+  Future<List<VocabularyItem>> fetchAndCacheVocabularyFromWk([
+    String? apiKey,
+  ]) async {
+    final key = apiKey ?? _apiKey;
+    if (key == null) throw Exception('API key not set');
+
+    final client = WkClient(key);
+    final assignments = await client.fetchAllAssignments(
+      subjectTypes: ['vocabulary'],
+    );
+
+    final unlocked = <int>{};
+    for (final a in assignments) {
+      final data = a['data'] as Map<String, dynamic>;
+      final sidRaw = data['subject_id'];
+      if (sidRaw == null) continue;
+      final sid = sidRaw is int ? sidRaw : int.tryParse(sidRaw.toString());
+      if (sid == null) continue;
+      final started = data['started_at'];
+      final srs = data['srs_stage'];
+      final isUnlocked = (started != null) || (srs != null && (srs as int) > 0);
+      if (isUnlocked) unlocked.add(sid);
+    }
+
+    if (unlocked.isEmpty) return [];
+
+    final subjects = await client.fetchSubjectsByIds(unlocked.toList());
+    final items = subjects
+        .where(
+          (s) =>
+              s['object'] == 'vocabulary' ||
+              (s['data'] != null &&
+                  (s['data'] as Map)['object_type'] == 'vocabulary'),
+        )
+        .map((s) => VocabularyItem.fromSubject(s))
+        .where((k) => k.characters.isNotEmpty && k.meanings.isNotEmpty)
+        .toList();
+
+    await saveVocabulary(items);
+    return items;
+  }
+}

lib/src/themes.dart

@@ -0,0 +1,129 @@
+import 'package:flutter/material.dart';
+
+class SrsColors {
+  final Color level1;
+  final Color level2;
+  final Color level3;
+  final Color level4;
+  final Color level5;
+  final Color level6;
+  final Color level7;
+  final Color level8;
+  final Color level9;
+
+  const SrsColors({
+    required this.level1,
+    required this.level2,
+    required this.level3,
+    required this.level4,
+    required this.level5,
+    required this.level6,
+    required this.level7,
+    required this.level8,
+    required this.level9,
+  });
+}
+
+extension CustomTheme on ThemeData {
+  SrsColors get srsColors {
+    if (brightness == Brightness.dark) {
+      return const SrsColors(
+        level1: Color(0xFFE57373), // red
+        level2: Color(0xFFFFB74D), // orange
+        level3: Color(0xFFFFD54F), // yellow
+        level4: Color(0xFFDCE775), // lime
+        level5: Color(0xFFAED581), // light green
+        level6: Color(0xFF81C784), // green
+        level7: Color(0xFF4DB6AC), // teal
+        level8: Color(0xFF4FC3F7), // light blue
+        level9: Color(0xFF7986CB), // indigo
+      );
+    } else if (colorScheme.primary == const Color(0xFF7B6D53)) { // Nier theme
+      return const SrsColors(
+        level1: Color(0xFFB71C1C), // dark red
+        level2: Color(0xFFD84315), // deep orange
+        level3: Color(0xFFF57F17), // yellow
+        level4: Color(0xFF9E9D24), // lime
+        level5: Color(0xFF558B2F), // light green
+        level6: Color(0xFF2E7D32), // green
+        level7: Color(0xFF00695C), // teal
+        level8: Color(0xFF0277BD), // light blue
+        level9: Color(0xFF283593), // indigo
+      );
+    } else { // Light theme
+      return const SrsColors(
+        level1: Colors.red,
+        level2: Colors.orange,
+        level3: Colors.yellow,
+        level4: Colors.lightGreen,
+        level5: Colors.green,
+        level6: Colors.teal,
+        level7: Colors.cyan,
+        level8: Colors.blue,
+        level9: Colors.purple,
+      );
+    }
+  }
+}
+
+class Themes {
+  static final dark = ThemeData(
+    colorScheme: const ColorScheme(
+      brightness: Brightness.dark,
+      primary: Color(0xFF90CAF9),
+      onPrimary: Colors.black,
+      secondary: Color(0xFFBBDEFB),
+      onSecondary: Colors.black,
+      tertiary: Color(0xFFA5D6A7),
+      onTertiary: Colors.black,
+      error: Color(0xFFEF9A9A),
+      onError: Colors.black,
+      surface: Color(0xFF121212),
+      onSurface: Colors.white,
+      surfaceContainer: Color(0xFF1E1E1E),
+      surfaceContainerHighest: Color(0xFF424242),
+      onSurfaceVariant: Colors.white70,
+    ),
+    useMaterial3: true,
+  );
+
+  static final light = ThemeData(
+    colorScheme: const ColorScheme(
+      brightness: Brightness.light,
+      primary: Color(0xFF1976D2),
+      onPrimary: Colors.white,
+      secondary: Color(0xFF42A5F5),
+      onSecondary: Colors.white,
+      tertiary: Color(0xFF66BB6A),
+      onTertiary: Colors.white,
+      error: Color(0xFFE57373),
+      onError: Colors.white,
+      surface: Color(0xFFFFFFFF),
+      onSurface: Colors.black,
+      surfaceContainer: Color(0xFFF5F5F5),
+      surfaceContainerHighest: Color(0xFFE0E0E0),
+      onSurfaceVariant: Colors.black54,
+    ),
+    useMaterial3: true,
+  );
+
+  static final nier = ThemeData(
+    colorScheme: const ColorScheme(
+      brightness: Brightness.light,
+      primary: Color(0xFF7B6D53),
+      onPrimary: Colors.white,
+      secondary: Color(0xFFA99A7E),
+      onSecondary: Colors.white,
+      tertiary: Color(0xFFA99A7E),
+      onTertiary: Colors.white,
+      error: Color(0xFFD32F2F),
+      onError: Colors.white,
+      surface: Color(0xFFCFCBAA),
+      onSurface: Color(0xFF333333),
+      surfaceContainer: Color(0xFFBDB898),
+      surfaceContainerHighest: Color(0xFFA8A388),
+      onSurfaceVariant: Color(0xFF545454),
+    ),
+    useMaterial3: true,
+  );
+}

lib/src/widgets/options_grid.dart

@@ -5,6 +5,10 @@ class OptionsGrid extends StatelessWidget {
   final void Function(String) onSelected;
   final Color? buttonColor;
   final Color? textColor;
+  final bool isDisabled;
+  final String? selectedOption;
+  final List<String>? correctAnswers;
+  final bool showResult;
 
   const OptionsGrid({
     super.key,
@@ -12,6 +16,10 @@ class OptionsGrid extends StatelessWidget {
     required this.onSelected,
     this.buttonColor,
     this.textColor,
+    this.isDisabled = false,
+    this.selectedOption,
+    this.correctAnswers,
+    this.showResult = false,
   });
 
   @override
@@ -27,13 +35,24 @@ class OptionsGrid extends StatelessWidget {
       runSpacing: 10,
       alignment: WrapAlignment.center,
       children: options.map((o) {
+        Color currentButtonColor = bg;
+        Color currentTextColor = fg;
+
+        if (showResult) {
+          if (correctAnswers != null && correctAnswers!.contains(o)) {
+            currentButtonColor = theme.colorScheme.tertiary;
+          } else if (o == selectedOption) {
+            currentButtonColor = theme.colorScheme.error;
+          }
+        }
+
         return SizedBox(
           width: 160,
           child: ElevatedButton(
-            onPressed: () => onSelected(o),
+            onPressed: isDisabled ? null : () => onSelected(o),
             style: ElevatedButton.styleFrom(
-              backgroundColor: bg,
-              foregroundColor: fg,
+              backgroundColor: currentButtonColor,
+              foregroundColor: currentTextColor,
               shape: RoundedRectangleBorder(
                 borderRadius: BorderRadius.circular(12),
               ),
@@ -41,7 +60,7 @@ class OptionsGrid extends StatelessWidget {
             ),
             child: Text(
               o,
-              style: TextStyle(fontSize: 20, color: fg),
+              style: theme.textTheme.titleMedium?.copyWith(color: currentTextColor),
               textAlign: TextAlign.center,
             ),
           ),
@@ -49,4 +68,4 @@ class OptionsGrid extends StatelessWidget {
       }).toList(),
     );
   }
-}
+}

pubspec.yaml

@@ -34,5 +34,4 @@ flutter_icons:
 flutter:
   uses-material-design: true
   assets:
-    - assets/sfx/confirm.mp3
-    - .env
+    - assets/sfx/confirm.mp3