feat: add sound effects, improved stroke recognition, instant locale switching with scramble text animation

- Add SoundManager with Web Audio API synthesized sounds (stroke error, drawing complete, session complete)
- Add sound effects toggle in settings (persisted via localStorage)
- Improve stroke recognition: curvature similarity, max point deviation, stroke length ratio checks
- Loosen thresholds for long strokes and first-stroke positioning
- Implement instant locale switching (no save required)
- Add ScrambleText component with character-by-character morphing animation
- Apply ScrambleText globally across all views, widgets, and dialogs
- Add i18n keys for sound effects settings (EN/DE/JA)

client/src/App.vue

@@ -12,7 +12,8 @@
       .d-flex.flex-column.h-100.pa-4
         .d-flex.align-center.mb-6.px-2
           img.mr-3(:src="logo" height="32" width="32" alt="Logo")
-          span.text-h6.font-weight-bold {{ $t('nav.menu') }}
+          span.text-h6.font-weight-bold
+            ScrambleText(:text="$t('nav.menu')")
 
         v-list.pa-0(nav bg-color="transparent")
           v-list-item.mb-2(
@@ -22,7 +23,8 @@
           )
             template(v-slot:prepend)
               v-icon(color="#00cec9" icon="mdi-view-dashboard")
-            v-list-item-title.font-weight-bold {{ $t('nav.dashboard') }}
+            v-list-item-title.font-weight-bold
+              ScrambleText(:text="$t('nav.dashboard')")
 
           v-list-item.mb-2(
             to="/collection"
@@ -31,7 +33,8 @@
           )
             template(v-slot:prepend)
               v-icon(color="#00cec9" icon="mdi-bookshelf")
-            v-list-item-title.font-weight-bold {{ $t('nav.collection') }}
+            v-list-item-title.font-weight-bold
+              ScrambleText(:text="$t('nav.collection')")
 
         v-divider.my-4.border-subtle
 
@@ -43,7 +46,7 @@
             @click="showSettings = true; drawer = false"
           )
             v-icon(start icon="mdi-cog")
-            | {{ $t('nav.settings') }}
+            ScrambleText(:text="$t('nav.settings')")
 
           v-btn.justify-start.px-4(
             variant="text"
@@ -53,7 +56,7 @@
             @click="manualSync"
           )
             v-icon(start icon="mdi-sync")
-            | {{ $t('nav.sync') }}
+            ScrambleText(:text="$t('nav.sync')")
 
           v-btn.justify-start.px-4.text-red-lighten-2(
             variant="text"
@@ -61,7 +64,7 @@
             @click="handleLogout"
           )
             v-icon(start icon="mdi-logout")
-            | {{ $t('nav.logout') }}
+            ScrambleText(:text="$t('nav.logout')")
     .parallax-bg(
       :style="parallaxStyle"
       :class="{ 'zooming': viewState === 'zooming' }"
@@ -103,13 +106,15 @@
               to="/"
               variant="text"
               :color="$route.path === '/' ? '#00cec9' : 'grey'"
-            ) {{ $t('nav.dashboard') }}
+            )
+              ScrambleText(:text="$t('nav.dashboard')")
 
             v-btn.mx-1(
               to="/collection"
               variant="text"
               :color="$route.path === '/collection' ? '#00cec9' : 'grey'"
-            ) {{ $t('nav.collection') }}
+            )
+              ScrambleText(:text="$t('nav.collection')")
 
             v-divider.mx-2.my-auto(vertical length="20" color="grey-darken-2")
 
@@ -169,8 +174,10 @@
         .login-content
           img.mb-4(:src="logo" height="64" width="64")
 
-          h1.text-h5.font-weight-bold.mb-2 {{ $t('hero.welcome') }}
+          h1.text-h5.font-weight-bold.mb-2
-          p.text-grey-lighten-1.text-body-2.mb-6 {{ $t('login.instruction') }}
+            ScrambleText(:text="$t('hero.welcome')")
+          p.text-grey-lighten-1.text-body-2.mb-6
+            ScrambleText(:text="$t('login.instruction')")
 
           v-text-field.mb-2(
             v-model="inputKey"
@@ -197,14 +204,17 @@
             height="44"
             :loading="viewState === 'authenticating'"
             @click="triggerLogin"
-          ) {{ $t('login.button') }}
+          )
+            ScrambleText(:text="$t('login.button')")
 
     v-dialog(v-model="showSettings" max-width="340")
       v-card.rounded-xl.pa-4.border-subtle(color="#1e1e24")
-        v-card-title.text-center.font-weight-bold {{ $t('settings.title') }}
+        v-card-title.text-center.font-weight-bold
+          ScrambleText(:text="$t('settings.title')")
 
         v-card-text.pt-4
-          .text-caption.text-grey.mb-2 {{ $t('settings.batchSize') }}
+          .text-caption.text-grey.mb-2
+            ScrambleText(:text="$t('settings.batchSize')")
           v-slider(
             v-model="tempBatchSize"
             :min="5"
@@ -215,9 +225,12 @@
             track-color="grey-darken-3"
           )
           .text-center.text-h5.font-weight-bold.text-teal-accent-3.mb-6
-            | {{ tempBatchSize }} {{ $t('settings.items') }}
+            | {{ tempBatchSize }}
+            |  
+            ScrambleText(:text="$t('settings.items')")
 
-          .text-caption.text-grey.mb-2 {{ $t('settings.drawingTolerance') }}
+          .text-caption.text-grey.mb-2
+            ScrambleText(:text="$t('settings.drawingTolerance')")
           v-slider(
             v-model="tempDrawingAccuracy"
             :min="1"
@@ -228,11 +241,16 @@
             track-color="grey-darken-3"
           )
           .d-flex.justify-space-between.text-caption.text-grey-lighten-1.mb-6.px-1
-            span {{ $t('settings.strict') }} (5)
+            span
+              ScrambleText(:text="$t('settings.strict')") 
+              |  (5)
             span.font-weight-bold.text-body-1(color="#00cec9") {{ tempDrawingAccuracy }}
-            span {{ $t('settings.loose') }} (20)
+            span
+              ScrambleText(:text="$t('settings.loose')")
+              |  (20)
 
-          .text-caption.text-grey.mb-2 {{ $t('settings.language') }}
+          .text-caption.text-grey.mb-2
+            ScrambleText(:text="$t('settings.language')")
 
           .lang-switch-wrapper.border-subtle.mb-2
             .lang-glider(:style="{ transform: `translateX(${localeIndex * 100}%)` }")
@@ -240,15 +258,29 @@
               v-for="l in availableLocales"
               :key="l"
               :class="{ 'active': tempLocale === l }"
-              @click="tempLocale = l"
+              @click="switchLocale(l)"
             ) {{ l.toUpperCase() }}
 
+          .d-flex.align-center.justify-space-between.mt-4.px-1
+            .text-caption.text-grey
+              ScrambleText(:text="$t('settings.soundEffects')")
+            v-switch(
+              v-model="soundEnabled"
+              color="cyan"
+              density="compact"
+              hide-details
+              inset
+            )
+              template(v-slot:label)
+                ScrambleText(:text="soundEnabled ? $t('settings.on') : $t('settings.off')")
+
         v-card-actions.mt-2
           v-btn.text-white(
             block
             color="#2f3542"
             @click="saveSettings"
-          ) {{ $t('settings.save') }}
+          )
+            ScrambleText(:text="$t('settings.save')")
 
     v-dialog(v-model="showLogoutDialog" max-width="320")
       v-card.rounded-xl.pa-4.border-subtle(color="#1e1e24")
@@ -256,10 +288,11 @@
           v-avatar.mb-3(color="red-darken-4" size="48")
             v-icon(icon="mdi-logout" size="24" color="red-lighten-1")
 
-          h3.text-h6.font-weight-bold.mb-2 {{ $t('nav.logout') }}?
+          h3.text-h6.font-weight-bold.mb-2
+            ScrambleText(:text="$t('nav.logout') + '?'")
 
           p.text-body-2.text-grey-lighten-1.px-2.mb-4
-            | {{ $t('alerts.logoutConfirm') }}
+            ScrambleText(:text="$t('alerts.logoutConfirm')")
 
         v-card-actions.d-flex.gap-2.pa-0.mt-2
           v-btn.flex-grow-1.text-capitalize(
@@ -267,19 +300,22 @@
             color="grey"
             height="40"
             @click="showLogoutDialog = false"
-          ) {{ $t('common.cancel') }}
+          )
+            ScrambleText(:text="$t('common.cancel')")
 
           v-btn.flex-grow-1.text-capitalize(
             color="red-accent-2"
             variant="flat"
             height="40"
             @click="confirmLogout"
-          ) {{ $t('nav.logout') }}
+          )
+            ScrambleText(:text="$t('nav.logout')")
 
     v-snackbar(v-model="snackbar.show" :color="snackbar.color" timeout="3000")
       | {{ snackbar.text }}
       template(v-slot:actions)
-        v-btn(variant="text" @click="snackbar.show = false") {{ $t('common.close') }}
+        v-btn(variant="text" @click="snackbar.show = false")
+          ScrambleText(:text="$t('common.close')")
 </template>
 
 <script setup>
@@ -291,6 +327,7 @@ import { useI18n } from 'vue-i18n';
 import { App as CapacitorApp } from '@capacitor/app';
 import { useAppStore } from '@/stores/appStore';
 import { checkForUpdates } from '@/utils/autoUpdate';
+import { SoundManager } from '@/utils/SoundManager';
 import logo from '@/assets/icon.svg';
 
 const drawer = ref(false);
@@ -313,6 +350,9 @@ const tempDrawingAccuracy = ref(store.drawingAccuracy);
 const availableLocales = ['en', 'de', 'ja'];
 const tempLocale = ref(locale.value);
 const localeIndex = computed(() => availableLocales.indexOf(tempLocale.value));
+const soundEnabled = ref(true);
+
+watch(inputKey, () => { errorMsg.value = ''; });
 
 const backgroundKanjis = [
   {
@@ -391,6 +431,7 @@ const handleMouseMove = (e) => {
 };
 
 onMounted(() => {
+  SoundManager.init();
   CapacitorApp.addListener('appStateChange', ({ isActive }) => {
     if (isActive) checkForUpdates();
   });
@@ -421,6 +462,7 @@ watch(showSettings, (isOpen) => {
     tempBatchSize.value = store.batchSize;
     tempDrawingAccuracy.value = store.drawingAccuracy;
     tempLocale.value = locale.value;
+    soundEnabled.value = !SoundManager.isMuted;
   }
 });
 
@@ -464,20 +506,23 @@ async function triggerLogin() {
   }
 }
 
+function switchLocale(l) {
+  tempLocale.value = l;
+  locale.value = l;
+  localStorage.setItem('zen_locale', l);
+}
+
 function saveSettings() {
   showSettings.value = false;
 
   setTimeout(() => {
-    if (locale.value !== tempLocale.value) {
-      locale.value = tempLocale.value;
-      localStorage.setItem('zen_locale', locale.value);
-    }
-
     store.saveSettings({
       batchSize: tempBatchSize.value,
       drawingAccuracy: tempDrawingAccuracy.value,
     });
 
+    SoundManager.setMuted(!soundEnabled.value);
+
     store.fetchQueue();
   }, 300);
 }

client/src/components/ScrambleText.vue

@@ -0,0 +1,79 @@
+<template lang="pug">
+  span {{ displayText }}
+</template>
+
+<script setup>
+import { ref, watch, onBeforeUnmount } from 'vue';
+
+const props = defineProps({
+  text: { type: String, required: true },
+});
+
+const displayText = ref(props.text);
+let frameId = null;
+
+const CHARS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZアイウエオカキクケコ漢字書道';
+const DURATION = 400; // total animation time in ms
+const STEPS_PER_CHAR = 3; // how many random chars before settling
+
+function scrambleTo(newText) {
+  if (frameId) cancelAnimationFrame(frameId);
+
+  const oldText = displayText.value;
+  const maxLen = Math.max(oldText.length, newText.length);
+  const startTime = performance.now();
+
+  // Each character position settles at a staggered time
+  const charDelay = DURATION / (maxLen || 1);
+
+  const tick = (now) => {
+    const elapsed = now - startTime;
+    let result = '';
+
+    for (let i = 0; i < maxLen; i++) {
+      const charSettleTime = i * charDelay;
+      const charElapsed = elapsed - charSettleTime;
+
+      if (i >= newText.length && elapsed > charSettleTime + charDelay) {
+        // This position should disappear — don't add anything
+        continue;
+      }
+
+      if (charElapsed >= charDelay) {
+        // This character has settled — show final
+        if (i < newText.length) result += newText[i];
+      } else if (charElapsed > 0) {
+        // This character is still scrambling
+        const step = Math.floor((charElapsed / charDelay) * STEPS_PER_CHAR);
+        if (step >= STEPS_PER_CHAR - 1 && i < newText.length) {
+          result += newText[i];
+        } else {
+          result += CHARS[Math.floor(Math.random() * CHARS.length)];
+        }
+      } else {
+        // Hasn't started yet — show old char or space
+        result += i < oldText.length ? oldText[i] : ' ';
+      }
+    }
+
+    displayText.value = result;
+
+    if (elapsed < DURATION + charDelay) {
+      frameId = requestAnimationFrame(tick);
+    } else {
+      displayText.value = newText;
+      frameId = null;
+    }
+  };
+
+  frameId = requestAnimationFrame(tick);
+}
+
+watch(() => props.text, (newVal) => {
+  scrambleTo(newVal);
+});
+
+onBeforeUnmount(() => {
+  if (frameId) cancelAnimationFrame(frameId);
+});
+</script>

client/src/components/dashboard/DashboardWidget.vue

@@ -14,8 +14,10 @@
         div
           .text-subtitle-1.font-weight-bold.d-flex.align-center.text-white(
             style="line-height: 1.2"
-          ) {{ title }}
+          )
-          .text-caption.text-grey(v-if="subtitle") {{ subtitle }}
+            ScrambleText(:text="title")
+          .text-caption.text-grey(v-if="subtitle")
+            ScrambleText(:text="subtitle")
 
       div.d-flex.align-center
         slot(name="header-right")

client/src/components/dashboard/WidgetAccuracy.vue

@@ -7,9 +7,11 @@
       div
         .text-h3.font-weight-bold.text-white {{ accuracyPercent }}%
         .text-caption.text-grey.mt-1
-          | {{ accuracy?.correct || 0 }} {{ $t('stats.correct') }}
+          | {{ accuracy?.correct || 0 }} 
+          ScrambleText(:text="$t('stats.correct')")
           span.mx-1 /
-          | {{ accuracy?.total || 0 }} {{ $t('stats.total') }}
+          | {{ accuracy?.total || 0 }} 
+          ScrambleText(:text="$t('stats.total')")
 
       v-progress-circular(
         :model-value="accuracyPercent"

client/src/components/dashboard/WidgetDistribution.vue

@@ -3,7 +3,7 @@
     .d-flex.align-center.justify-space-between.mb-4
       .text-subtitle-1.font-weight-bold.d-flex.align-center
         v-icon(color="secondary" start size="small") mdi-chart-bar
-        | {{ $t('stats.srsDistribution') }}
+        ScrambleText(:text="$t('stats.srsDistribution')")
       v-chip.font-weight-bold(
         size="x-small"
         color="white"

client/src/components/dashboard/WidgetForecast.vue

@@ -7,7 +7,7 @@
       div(v-for="(count, hour) in forecast" :key="hour")
         .d-flex.justify-space-between.align-center.mb-2.py-2.border-b-subtle(v-if="count > 0")
           span.text-body-2.text-grey-lighten-1
-            | {{ hour === 0 ? $t('stats.availableNow') : $t('stats.inHours', { n: hour }, hour) }}
+            ScrambleText(:text="hour === 0 ? $t('stats.availableNow') : $t('stats.inHours', { n: hour }, hour)")
 
           v-chip.font-weight-bold.text-primary(
             size="small"
@@ -15,7 +15,7 @@
           ) {{ count }}
 
     .fill-height.d-flex.align-center.justify-center.text-grey.text-center.pa-4(v-else)
-      | {{ $t('stats.noIncoming') }}
+      ScrambleText(:text="$t('stats.noIncoming')")
 </template>
 
 <script setup>
@@ -24,7 +24,7 @@ import { computed } from 'vue';
 import DashboardWidget from './DashboardWidget.vue';
 
 const props = defineProps({
-  forecast: { type: Object, default: () => ({}) },
+  forecast: { type: Array, default: () => [] },
 });
 
 const hasUpcoming = computed(() => props.forecast && props.forecast.some((c) => c > 0));

client/src/components/dashboard/WidgetGhosts.vue

@@ -24,7 +24,7 @@
           ) {{ ghost.accuracy }}%
 
       .text-center.py-2.text-caption.text-grey(v-else)
-        | {{ $t('stats.noGhosts') }}
+        ScrambleText(:text="$t('stats.noGhosts')")
 </template>
 
 <script setup>

client/src/components/dashboard/WidgetGuruMastery.vue

@@ -17,7 +17,8 @@
         )
 
         .text-caption.text-medium-emphasis.mt-2.text-right
-          | {{ masteredCount }} / {{ totalItems }} {{ $t('stats.items') }}
+          | {{ masteredCount }} / {{ totalItems }} 
+          ScrambleText(:text="$t('stats.items')")
 </template>
 
 <script setup>
@@ -33,7 +34,7 @@ const totalItems = computed(
   () => Object.values(props.distribution || {}).reduce((a, b) => a + b, 0),
 );
 const masteredCount = computed(
-  () => (props.distribution || {})[6] || 0,
+  () => [6, 7, 8, 9, 10].reduce((sum, lvl) => sum + ((props.distribution || {})[lvl] || 0), 0),
 );
 const masteryPercent = computed(
   () => (totalItems.value === 0 ? 0 : Math.round((masteredCount.value / totalItems.value) * 100)),

client/src/components/dashboard/WidgetHeatmap.vue

@@ -5,13 +5,15 @@
   )
     template(#header-right)
       .legend-container
-        span.text-caption.text-medium-emphasis.mr-1 {{ $t('stats.less') }}
+        span.text-caption.text-medium-emphasis.mr-1
+          ScrambleText(:text="$t('stats.less')")
         .legend-box.level-0
         .legend-box.level-1
         .legend-box.level-2
         .legend-box.level-3
         .legend-box.level-4
-        span.text-caption.text-medium-emphasis.ml-1 {{ $t('stats.more') }}
+        span.text-caption.text-medium-emphasis.ml-1
+          ScrambleText(:text="$t('stats.more')")
 
     .heatmap-container
       .heatmap-year
@@ -25,7 +27,8 @@
                 )
               .text-center
                 .font-weight-bold {{ formatDate(day.date) }}
-                div {{ $t('stats.reviewsCount', { count: day.count }) }}
+                div
+                  ScrambleText(:text="$t('stats.reviewsCount', { count: day.count })")
 </template>
 
 <script setup>

client/src/components/dashboard/WidgetStreak.vue

@@ -19,7 +19,8 @@
       .d-flex.align-end.mb-3
         .text-h3.font-weight-bold.text-white.mr-2(style="line-height: 1")
           | {{ streak?.current || 0 }}
-        .text-body-1.text-grey.mb-1 {{ $t('stats.days') }}
+        .text-body-1.text-grey.mb-1
+          ScrambleText(:text="$t('stats.days')")
 
       .d-flex.justify-space-between.align-center.px-1
         .d-flex.flex-column.align-center(

client/src/components/dashboard/WidgetWelcome.vue

@@ -1,9 +1,11 @@
 <template lang="pug">
   .grid-area-full.text-center.mb-8.zen-wrapper
-    .text-h3.font-weight-bold.mb-2.text-white.letter-spacing-small {{ $t('hero.welcome') }}
+    .text-h3.font-weight-bold.mb-2.text-white.letter-spacing-small
+      ScrambleText(:text="$t('hero.welcome')")
     .text-subtitle-1.text-grey-lighten-1.mb-10(
       style="max-width: 600px; margin-inline: auto;"
-    ) {{ $t('hero.subtitle') }}
+    )
+      ScrambleText(:text="$t('hero.subtitle')")
 
     .d-flex.justify-center.align-stretch.flex-wrap.ga-6.mb-8
 
@@ -21,9 +23,9 @@
 
           .d-flex.flex-column.align-start.mr-auto
             .text-purple-lighten-1.text-h6.font-weight-bold.line-height-tight
-              | {{ $t('hero.lessons') }}
+              ScrambleText(:text="$t('hero.lessons')")
             .text-purple-accent-1.text-caption.font-weight-regular.opacity-80
-              | {{ $t('hero.newContent') }}
+              ScrambleText(:text="$t('hero.newContent')")
 
           .zen-counter.bg-purple-accent-2.text-black.ml-4
             | {{ lessonCount }}
@@ -43,9 +45,9 @@
 
             .d-flex.flex-column.align-start.mr-auto
               .text-cyan-lighten-1.text-h6.font-weight-bold.line-height-tight
-                | {{ queueLength > 0 ? $t('hero.start') : $t('hero.noReviews') }}
+                ScrambleText(:text="queueLength > 0 ? $t('hero.start') : $t('hero.noReviews')")
               .text-cyan-accent-1.text-caption.font-weight-regular.opacity-80
-                | {{ queueLength > 0 ? $t('hero.readyToReview') : $t('hero.allCaughtUp') }}
+                ScrambleText(:text="queueLength > 0 ? $t('hero.readyToReview') : $t('hero.allCaughtUp')")
 
             v-fade-transition
               .zen-counter.bg-cyan-accent-2.text-black.ml-4(v-if="queueLength > 0")
@@ -59,14 +61,16 @@
           variant="text"
           prepend-icon="mdi-sort-ascending"
           :ripple="false"
-        ) {{ $t('hero.prioritize', { count: lowerLevelCount }) }}
+        )
+          ScrambleText(:text="$t('hero.prioritize', { count: lowerLevelCount })")
 
       v-fade-transition
         .text-caption.text-grey-darken-1.font-weight-medium.d-flex.align-center.mt-2(
           v-if="queueLength === 0 && !hasLowerLevels && nextReviewTime"
         )
           v-icon.mr-2(size="small" icon="mdi-clock-outline")
-          span {{ $t('hero.nextIn') }} {{ nextReviewTime }}
+          span
+            ScrambleText(:text="$t('hero.nextIn') + ' ' + nextReviewTime")
 </template>
 
 <script setup>
@@ -79,14 +83,14 @@ const props = defineProps({
   lessonCount: { type: Number, default: 0 },
   hasLowerLevels: { type: Boolean, default: false },
   lowerLevelCount: { type: Number, default: 0 },
-  forecast: { type: Object, default: () => ({}) },
+  forecast: { type: Array, default: () => [] },
 });
 defineEmits(['start']);
 
 const { t } = useI18n();
 
 const nextReviewTime = computed(() => {
-  if (!props.forecast || Object.keys(props.forecast).length === 0) return null;
+  if (!props.forecast || props.forecast.length === 0) return null;
   try {
     const idx = props.forecast.findIndex((c) => c > 0);
     if (idx === -1) return null;

client/src/main.js

@@ -51,8 +51,11 @@ const vuetify = createVuetify({
   icons: { defaultSet: 'mdi', aliases, sets: { mdi } },
 });
 
+import ScrambleText from '@/components/ScrambleText.vue';
+
 app.use(pinia);
 app.use(router);
 app.use(vuetify);
 app.use(i18n);
+app.component('ScrambleText', ScrambleText);
 app.mount('#app');

client/src/plugins/i18n.js

@@ -44,8 +44,13 @@ const messages = {
       learned: "You've learned {n} new kanji.",
       components: 'Components',
       observe: 'Observe Stroke Order',
+      replay: 'Replay',
       trace: 'Trace',
       drawStep: 'Draw ({n}/{total})',
+      sectionMeaning: 'Meaning',
+      sectionMnemonic: 'Memory Aid',
+      sectionReadings: 'Readings',
+      learnedKanji: 'Kanji Learned',
       backToDashboard: 'Back to Dashboard',
     },
     hero: {
@@ -70,6 +75,7 @@ const messages = {
       next24: 'Next 24h',
       availableNow: 'Available Now',
       inHours: 'In {n} hour | In {n} hours',
+      inDays: 'In {n} day | In {n} days',
       noIncoming: 'No reviews incoming for 24 hours.',
       items: 'items',
       reviewsCount: '{count} reviews',
@@ -96,6 +102,9 @@ const messages = {
       strict: 'Strict',
       loose: 'Loose',
       save: 'Save & Close',
+      soundEffects: 'Sound Effects',
+      on: 'On',
+      off: 'Off',
     },
     review: {
       meaning: 'Meaning',
@@ -109,6 +118,9 @@ const messages = {
       next: 'NEXT',
       sessionComplete: 'Session Complete!',
       levelup: 'You leveled up your Kanji skills.',
+      levelsUp: '{n} leveled up',
+      levelsDown: '{n} leveled down',
+      results: 'Results',
       back: 'Back to Collection',
       caughtUp: 'All Caught Up!',
       noReviews: 'No reviews available right now.',
@@ -174,8 +186,13 @@ const messages = {
       learned: 'Du hast {n} neue Kanji gelernt.',
       components: 'Komponenten',
       observe: 'Strichfolge beobachten',
+      replay: 'Wiederholen',
       trace: 'Nachzeichnen',
       drawStep: 'Zeichnen ({n}/{total})',
+      sectionMeaning: 'Bedeutung',
+      sectionMnemonic: 'Merkhilfe',
+      sectionReadings: 'Lesungen',
+      learnedKanji: 'Gelernte Kanji',
       backToDashboard: 'Zurück zur Übersicht',
     },
     hero: {
@@ -200,6 +217,7 @@ const messages = {
       next24: 'Nächste 24h',
       availableNow: 'Jetzt verfügbar',
       inHours: 'In {n} Stunde | In {n} Stunden',
+      inDays: 'In {n} Tag | In {n} Tagen',
       noIncoming: 'Keine Reviews in den nächsten 24h.',
       items: 'Einträge',
       reviewsCount: '{count} Reviews',
@@ -226,6 +244,9 @@ const messages = {
       strict: 'Strikt',
       loose: 'Locker',
       save: 'Speichern & Schließen',
+      soundEffects: 'Soundeffekte',
+      on: 'An',
+      off: 'Aus',
     },
     review: {
       meaning: 'Bedeutung',
@@ -239,6 +260,9 @@ const messages = {
       next: 'WEITER',
       sessionComplete: 'Sitzung beendet!',
       levelup: 'Du hast deine Kanji-Skills verbessert.',
+      levelsUp: '{n} aufgestiegen',
+      levelsDown: '{n} abgestiegen',
+      results: 'Ergebnisse',
       back: 'Zurück zur Sammlung',
       caughtUp: 'Alles erledigt!',
       noReviews: 'Gerade keine Reviews verfügbar.',
@@ -304,8 +328,13 @@ const messages = {
       learned: '{n}個の新しい漢字を覚えました。',
       components: '構成要素',
       observe: '書き順を見る',
+      replay: 'もう一度',
       trace: 'なぞる',
       drawStep: '書く ({n}/{total})',
+      sectionMeaning: '意味',
+      sectionMnemonic: '覚え方',
+      sectionReadings: '読み方',
+      learnedKanji: '学んだ漢字',
       backToDashboard: 'ダッシュボードに戻る',
     },
     hero: {
@@ -330,6 +359,7 @@ const messages = {
       next24: '今後24時間',
       availableNow: '今すぐ可能',
       inHours: '{n}時間後',
+      inDays: '{n}日後',
       noIncoming: '24時間以内のレビューはありません。',
       items: '個',
       reviewsCount: '{count} レビュー',
@@ -356,6 +386,9 @@ const messages = {
       strict: '厳しい',
       loose: '甘い',
       save: '保存して閉じる',
+      soundEffects: '効果音',
+      on: 'オン',
+      off: 'オフ',
     },
     review: {
       meaning: '意味',
@@ -369,6 +402,9 @@ const messages = {
       next: '次へ',
       sessionComplete: 'セッション完了！',
       levelup: '漢字力がアップしました。',
+      levelsUp: '{n}個昇格',
+      levelsDown: '{n}個降格',
+      results: '結果',
       back: 'コレクションに戻る',
       caughtUp: '完了しました！',
       noReviews: '現在レビューするものはありません。',

client/src/utils/KanjiController.js

@@ -1,3 +1,5 @@
+import { SoundManager } from './SoundManager.js';
+
 export const KANJI_CONSTANTS = {
   BASE_SIZE: 109,
   SVG_NS: 'http://www.w3.org/2000/svg',
@@ -11,7 +13,7 @@ export const KANJI_CONSTANTS = {
   SAMPLE_POINTS: 60,
 
   VALIDATION: {
-    SAMPLES: 10,
+    SAMPLES: 20,
   },
 
   COLORS: {
@@ -323,12 +325,16 @@ export class KanjiController {
         this.clearCanvas(this.ctx.hint);
 
         if (this.currentStrokeIdx >= this.paths.length) {
+          SoundManager.playDrawingComplete();
           this.onComplete();
-        } else if (this.autoHint) {
+        } else {
-          this.showHint();
+          if (this.autoHint) {
+            this.showHint();
+          }
         }
       });
     } else {
+      SoundManager.playStrokeError();
       this.mistakes += 1;
       this.animateErrorFade(this.userPath, () => {
         this.redrawAllPerfectStrokes();
@@ -346,27 +352,171 @@ export class KanjiController {
     const len = pathEl.getTotalLength();
     const { SAMPLES } = KANJI_CONSTANTS.VALIDATION;
 
-    const avgDistThreshold = this.accuracy * 0.8;
-    const startEndThreshold = this.accuracy * 2.5;
-
-    const targetStart = pathEl.getPointAtLength(0);
-    const targetEnd = pathEl.getPointAtLength(len);
-
     const dist = (p1, p2) => Math.hypot(p1.x - p2.x, p1.y - p2.y);
 
-    if (dist(userPts[0], targetStart) > startEndThreshold) return false;
+    // ── 1. Start / end point check ──────────────────
-    if (dist(userPts[userPts.length - 1], targetEnd) > startEndThreshold) return false;
+    const targetStart = pathEl.getPointAtLength(0);
+    const targetEnd = pathEl.getPointAtLength(len);
+    const userStart = userPts[0];
+    const userEnd = userPts[userPts.length - 1];
 
+    const isFirstStroke = this.currentStrokeIdx === 0;
+    const startThreshold = this.accuracy * (isFirstStroke ? 3.5 : 2.5);
+    // End tolerance scales with stroke length — long strokes get more forgiveness
+    const lengthBonus = Math.min(len / 30, 1.5);
+    const endThreshold = this.accuracy * (2.5 + lengthBonus);
+
+    if (dist(userStart, targetStart) > startThreshold) return false;
+    if (dist(userEnd, targetEnd) > endThreshold) return false;
+
+    // ── 2. Overall direction check ──────────────────
+    const userAngle = Math.atan2(userEnd.y - userStart.y, userEnd.x - userStart.x);
+    const targetAngle = Math.atan2(targetEnd.y - targetStart.y, targetEnd.x - targetStart.x);
+    const angleDiff = KanjiController.normalizeAngle(userAngle - targetAngle);
+
+    // Reject if direction is off by more than 90 degrees
+    if (angleDiff > Math.PI / 2) return false;
+
+    // ── 3. Orientation classification guard ─────────
+    const userOrientation = KanjiController.classifyOrientation(userStart, userEnd);
+    const targetOrientation = KanjiController.classifyOrientation(targetStart, targetEnd);
+
+    // Only block if both strokes are clearly H or V (not diagonal or dot)
+    if (userOrientation !== 'other' && targetOrientation !== 'other'
+        && userOrientation !== targetOrientation) {
+      return false;
+    }
+
+    // ── 4. Sequential sample comparison ─────────────
+    const userResampled = KanjiController.resamplePoints(userPts, SAMPLES + 1);
     let totalError = 0;
-    const sampleCount = SAMPLES + 1;
+    let maxError = 0;
 
-    totalError = Array.from({ length: sampleCount }).reduce((acc, _, i) => {
+    for (let i = 0; i <= SAMPLES; i++) {
-      const targetPt = pathEl.getPointAtLength((i / SAMPLES) * len);
+      const t = i / SAMPLES;
-      const minD = userPts.reduce((min, up) => Math.min(min, dist(targetPt, up)), Infinity);
+      const targetPt = pathEl.getPointAtLength(t * len);
-      return acc + minD;
+      const userPt = userResampled[i];
-    }, 0);
+      const d = dist(targetPt, userPt);
+      totalError += d;
+      if (d > maxError) maxError = d;
+    }
 
-    return (totalError / sampleCount) < avgDistThreshold;
+    const avgError = totalError / (SAMPLES + 1);
+    const avgDistThreshold = this.accuracy * 1.0;
+    const maxDistThreshold = this.accuracy * 3.5;
+
+    if (avgError > avgDistThreshold) return false;
+    // No single point should be wildly off — catches "right average, wrong shape"
+    if (maxError > maxDistThreshold) return false;
+
+    // ── 4b. Stroke length ratio ─────────────────────
+    let userLen = 0;
+    for (let i = 1; i < userPts.length; i++) {
+      userLen += dist(userPts[i - 1], userPts[i]);
+    }
+    const lengthRatio = userLen / len;
+    // User stroke should be between 30% and 300% of target length
+    // Long straight strokes especially benefit from the upper bound
+    if (lengthRatio < 0.3 || lengthRatio > 3.0) return false;
+
+    // ── 4c. Curvature similarity ────────────────────
+    const targetCurvature = KanjiController.measureCurvature(
+      userResampled.map((_, i) => {
+        const t = i / SAMPLES;
+        const pt = pathEl.getPointAtLength(t * len);
+        return { x: pt.x, y: pt.y };
+      }),
+    );
+    const userCurvature = KanjiController.measureCurvature(userPts);
+
+    // If target is clearly curved but user drew straight (or vice versa)
+    const curvatureDiff = Math.abs(targetCurvature - userCurvature);
+    // Scale threshold: strict = 0.2, loose = 0.5
+    const curvatureThreshold = 0.15 + (this.accuracy / 20) * 0.35;
+    if (curvatureDiff > curvatureThreshold) return false;
+
+    // ── 5. Endpoint direction check (hook detection) ─
+    const tailFraction = 0.2;
+    const targetTailStart = pathEl.getPointAtLength(len * (1 - tailFraction));
+    const targetTailAngle = Math.atan2(
+      targetEnd.y - targetTailStart.y,
+      targetEnd.x - targetTailStart.x,
+    );
+
+    // Check if target has a significant direction change at the end (hook)
+    const mainTargetAngle = Math.atan2(
+      targetEnd.y - targetStart.y,
+      targetEnd.x - targetStart.x,
+    );
+    const targetHookAngle = KanjiController.normalizeAngle(targetTailAngle - mainTargetAngle);
+    const hasHook = targetHookAngle > Math.PI / 6; // > 30 degrees = hook
+
+    if (hasHook) {
+      // User must also have a direction change in the last portion
+      const tailIdx = Math.max(0, Math.floor(userPts.length * (1 - tailFraction)));
+      const userTailStart = userPts[tailIdx];
+      const userTailAngle = Math.atan2(
+        userEnd.y - userTailStart.y,
+        userEnd.x - userTailStart.x,
+      );
+      const mainUserAngle = Math.atan2(
+        userEnd.y - userStart.y,
+        userEnd.x - userStart.x,
+      );
+      const userHookAngle = KanjiController.normalizeAngle(userTailAngle - mainUserAngle);
+
+      // User's hook should be at least half as pronounced as the target's
+      // but use a generous threshold scaled by accuracy
+      const hookThreshold = Math.max(Math.PI / 12, targetHookAngle * 0.4);
+      if (userHookAngle < hookThreshold) {
+        // Only reject on strict accuracy (< 12), forgive on loose settings
+        if (this.accuracy < 12) return false;
+      }
+    }
+
+    return true;
+  }
+
+  // ── Static helpers for stroke validation ────────────
+
+  static normalizeAngle(angle) {
+    let a = Math.abs(angle);
+    if (a > Math.PI) a = 2 * Math.PI - a;
+    return a;
+  }
+
+  static classifyOrientation(start, end) {
+    const dx = Math.abs(end.x - start.x);
+    const dy = Math.abs(end.y - start.y);
+    const totalDist = Math.hypot(dx, dy);
+
+    // Very short strokes (dots) — don't classify
+    if (totalDist < 5) return 'other';
+
+    const ratio = dx / (dy || 0.001);
+    if (ratio > 2.5) return 'horizontal';
+    if (ratio < 0.4) return 'vertical';
+    return 'other'; // diagonal or ambiguous
+  }
+
+  static measureCurvature(points) {
+    if (points.length < 3) return 0;
+
+    // Curvature = ratio of actual path length to straight-line distance
+    // A perfectly straight line = 0, a semicircle ≈ 0.57
+    let pathLen = 0;
+    for (let i = 1; i < points.length; i++) {
+      pathLen += Math.hypot(points[i].x - points[i - 1].x, points[i].y - points[i - 1].y);
+    }
+
+    const straightDist = Math.hypot(
+      points[points.length - 1].x - points[0].x,
+      points[points.length - 1].y - points[0].y,
+    );
+
+    if (straightDist < 1) return 0; // dot-like stroke
+    // Returns 0 for straight, >0 for curved (ratio - 1)
+    return Math.max(0, (pathLen / straightDist) - 1);
   }
 
   animateErrorFade(userPath, onComplete) {

client/src/utils/SoundManager.js

@@ -0,0 +1,177 @@
+/**
+ * SoundManager — Web Audio API synthesized sounds for ZenKanji.
+ *
+ * All sounds are generated programmatically (no external files).
+ * Designed to be subtle, smooth, and non-annoying.
+ */
+
+let audioCtx = null;
+let muted = false;
+const MASTER_VOLUME = 0.15;
+
+function getCtx() {
+  if (!audioCtx) {
+    audioCtx = new (window.AudioContext || window.webkitAudioContext)();
+  }
+  return audioCtx;
+}
+
+function ensureResumed() {
+  const ctx = getCtx();
+  if (ctx.state === 'suspended') ctx.resume();
+  return ctx;
+}
+
+/**
+ * Play a soft "pop" — stroke accepted.
+ * Short sine wave with quick pitch drop, very gentle.
+ */
+function playStrokeCorrect() {
+  if (muted) return;
+  const ctx = ensureResumed();
+  const now = ctx.currentTime;
+
+  const osc = ctx.createOscillator();
+  const gain = ctx.createGain();
+
+  osc.type = 'sine';
+  osc.frequency.setValueAtTime(880, now);
+  osc.frequency.exponentialRampToValueAtTime(440, now + 0.08);
+
+  gain.gain.setValueAtTime(MASTER_VOLUME * 0.6, now);
+  gain.gain.exponentialRampToValueAtTime(0.001, now + 0.12);
+
+  osc.connect(gain);
+  gain.connect(ctx.destination);
+
+  osc.start(now);
+  osc.stop(now + 0.12);
+}
+
+/**
+ * Play a soft low thud — stroke rejected.
+ * Very short, low frequency, barely audible. Not jarring.
+ */
+function playStrokeError() {
+  if (muted) return;
+  const ctx = ensureResumed();
+  const now = ctx.currentTime;
+
+  const osc = ctx.createOscillator();
+  const gain = ctx.createGain();
+
+  osc.type = 'sine';
+  osc.frequency.setValueAtTime(200, now);
+  osc.frequency.exponentialRampToValueAtTime(120, now + 0.15);
+
+  gain.gain.setValueAtTime(MASTER_VOLUME * 0.4, now);
+  gain.gain.exponentialRampToValueAtTime(0.001, now + 0.15);
+
+  osc.connect(gain);
+  gain.connect(ctx.destination);
+
+  osc.start(now);
+  osc.stop(now + 0.15);
+}
+
+/**
+ * Play a pleasant ascending two-tone chime — drawing complete (all strokes done).
+ */
+function playDrawingComplete() {
+  if (muted) return;
+  const ctx = ensureResumed();
+  const now = ctx.currentTime;
+
+  [523.25, 659.25].forEach((freq, i) => {
+    const osc = ctx.createOscillator();
+    const gain = ctx.createGain();
+
+    osc.type = 'sine';
+    osc.frequency.value = freq;
+
+    const start = now + i * 0.1;
+    gain.gain.setValueAtTime(0, start);
+    gain.gain.linearRampToValueAtTime(MASTER_VOLUME * 0.7, start + 0.03);
+    gain.gain.exponentialRampToValueAtTime(0.001, start + 0.3);
+
+    osc.connect(gain);
+    gain.connect(ctx.destination);
+
+    osc.start(start);
+    osc.stop(start + 0.3);
+  });
+}
+
+/**
+ * Play a gentle three-tone ascending arpeggio — session/lesson complete.
+ * C5 → E5 → G5, soft and satisfying.
+ */
+function playSessionComplete() {
+  if (muted) return;
+  const ctx = ensureResumed();
+  const now = ctx.currentTime;
+
+  [523.25, 659.25, 783.99].forEach((freq, i) => {
+    const osc = ctx.createOscillator();
+    const gain = ctx.createGain();
+
+    osc.type = 'triangle';
+    osc.frequency.value = freq;
+
+    const start = now + i * 0.12;
+    gain.gain.setValueAtTime(0, start);
+    gain.gain.linearRampToValueAtTime(MASTER_VOLUME * 0.8, start + 0.04);
+    gain.gain.exponentialRampToValueAtTime(0.001, start + 0.5);
+
+    osc.connect(gain);
+    gain.connect(ctx.destination);
+
+    osc.start(start);
+    osc.stop(start + 0.5);
+  });
+}
+
+/**
+ * Play a subtle click — button press / UI interaction.
+ */
+function playClick() {
+  if (muted) return;
+  const ctx = ensureResumed();
+  const now = ctx.currentTime;
+
+  const osc = ctx.createOscillator();
+  const gain = ctx.createGain();
+
+  osc.type = 'sine';
+  osc.frequency.value = 1000;
+
+  gain.gain.setValueAtTime(MASTER_VOLUME * 0.3, now);
+  gain.gain.exponentialRampToValueAtTime(0.001, now + 0.05);
+
+  osc.connect(gain);
+  gain.connect(ctx.destination);
+
+  osc.start(now);
+  osc.stop(now + 0.05);
+}
+
+export const SoundManager = {
+  playStrokeCorrect,
+  playStrokeError,
+  playDrawingComplete,
+  playSessionComplete,
+  playClick,
+
+  get isMuted() {
+    return muted;
+  },
+
+  setMuted(val) {
+    muted = val;
+    localStorage.setItem('zen_sound_muted', val ? '1' : '0');
+  },
+
+  init() {
+    muted = localStorage.getItem('zen_sound_muted') === '1';
+  },
+};

client/src/views/Collection.vue

@@ -13,14 +13,17 @@
       clearable
     )
 
-    .text-center.mt-10(v-if="loading") {{ $t('collection.loading') }}
+    .text-center.mt-10(v-if="loading")
+      ScrambleText(:text="$t('collection.loading')")
 
     .text-center.mt-10.text-grey-lighten-1(
       v-else-if="!loading && Object.keys(groupedItems).length === 0"
     )
       v-icon.mb-4(size="64" color="grey-darken-2") mdi-text-search-variant
-      .text-h6 {{ $t('collection.noMatches') }}
+      .text-h6
-      .text-body-2 {{ $t('collection.tryDifferent') }}
+        ScrambleText(:text="$t('collection.noMatches')")
+      .text-body-2
+        ScrambleText(:text="$t('collection.tryDifferent')")
 
     .mb-6.fade-slide-up(
       v-else
@@ -28,7 +31,7 @@
       :key="level"
     )
       .text-subtitle-2.text-grey.mb-2.font-weight-bold.ml-1
-        | {{ $t('collection.levelHeader') }} {{ level }}
+        ScrambleText(:text="$t('collection.levelHeader') + ' ' + level")
 
       .kanji-grid
         .kanji-card(
@@ -76,7 +79,8 @@
     )
       v-card.pa-4.pt-6.text-center.rounded-xl.border-subtle(color="#1e1e24")
         .d-flex.justify-space-between.align-center.px-2.mb-2
-          .text-caption.text-grey {{ $t('review.level') }} {{ selectedItem?.level }}
+          .text-caption.text-grey
+            ScrambleText(:text="$t('review.level') + ' ' + selectedItem?.level")
           v-chip.font-weight-bold(
             size="x-small"
             :color="getSRSColor(selectedItem?.srsLevel)"
@@ -94,7 +98,7 @@
 
         .radical-section.mb-4(v-if="selectedItem?.radicals?.length")
           .text-caption.text-grey-darken-1.text-uppercase.mb-3.font-weight-bold
-            |{{ $t('lesson.components') }}
+            ScrambleText(:text="$t('lesson.components')")
           .d-flex.flex-wrap.gap-3.justify-center
             v-sheet.radical-chip(
               v-for="rad in selectedItem.radicals" :key="rad.meaning")
@@ -106,20 +110,24 @@
 
         .readings-container.mb-4
           .reading-group(v-if="hasReading(selectedItem?.onyomi)")
-            .reading-label {{ $t('collection.onyomi') }}
+            .reading-label
+              ScrambleText(:text="$t('collection.onyomi')")
             .reading-value {{ selectedItem?.onyomi.join(', ') }}
 
           .reading-group(v-if="hasReading(selectedItem?.kunyomi)")
-            .reading-label {{ $t('collection.kunyomi') }}
+            .reading-label
+              ScrambleText(:text="$t('collection.kunyomi')")
             .reading-value {{ selectedItem?.kunyomi.join(', ') }}
 
           .reading-group(v-if="hasReading(selectedItem?.nanori)")
-            .reading-label {{ $t('collection.nanori') }}
+            .reading-label
+              ScrambleText(:text="$t('collection.nanori')")
             .reading-value {{ selectedItem?.nanori.join(', ') }}
 
         .px-2.mb-4(v-if="selectedItem?.stats?.total > 0")
           .d-flex.justify-space-between.align-center.mb-1
-            .text-caption.text-grey {{ $t('stats.accuracy') }}
+            .text-caption.text-grey
+              ScrambleText(:text="$t('stats.accuracy')")
             .text-caption.font-weight-bold {{ accuracyStats.text }}
           v-progress-linear(
             :model-value="accuracyStats.percent"
@@ -134,16 +142,15 @@
                block
                color="#2f3542"
                @click="showModal = false"
-             ) {{ $t('collection.close') }}
+             )
+               ScrambleText(:text="$t('collection.close')")
           v-col.pl-2(cols="6")
              v-btn.text-black(
                block
                color="purple-accent-2"
                @click="redoLesson"
              )
-              | {{ selectedItem?.srsLevel === 0
+              ScrambleText(:text="selectedItem?.srsLevel === 0 ? $t('collection.startLesson') : $t('collection.redoLesson')")
-              |    ? $t('collection.startLesson')
-              |    : $t('collection.redoLesson') }}
 </template>
 
 <script setup>
@@ -264,6 +271,6 @@ const getNextReviewText = (dateStr, srsLvl) => {
   if (diffHrs < 24) return t('stats.inHours', { n: diffHrs }, diffHrs);
 
   const diffDays = Math.floor(diffHrs / 24);
-  return `Next: ${diffDays}d`;
+  return t('stats.inDays', { n: diffDays }, diffDays);
 };
 </script>

client/src/views/Lesson.vue

@@ -2,7 +2,8 @@
   v-container.page-container-center.fill-height
     .d-flex.flex-column.justify-center.align-center.fill-height(v-if="loading")
       v-progress-circular(indeterminate color="primary" size="64")
-      .text-body-1.text-grey.mt-4 {{ $t('review.loading') }}
+      .text-body-1.text-grey.mt-4
+        ScrambleText(:text="$t('review.loading')")
 
     v-card.lesson-card(
       v-else-if="currentItem"
@@ -13,23 +14,39 @@
         .text-caption.text-grey-darken-1.font-weight-bold
           | {{ sessionDone + 1 }} / {{ sessionTotal }}
         v-spacer
-        v-chip.font-weight-bold(
+        .stepper-spacer
-          size="small"
+
-          :color="phaseColor"
+      .lesson-stepper.px-4.py-3
-          variant="tonal"
+        template(v-for="(step, i) in stepperSteps" :key="step.key")
-        ) {{ phaseLabel }}
+          .lesson-stepper__step(:class="{ 'is-active': step.active, 'is-done': step.done }")
+            .lesson-stepper__dot
+              v-icon(v-if="step.done" size="14" color="white") mdi-check
+              span(v-else) {{ i + 1 }}
+            .lesson-stepper__label {{ step.label }}
+          .lesson-stepper__line(
+            v-if="i < stepperSteps.length - 1"
+            :class="{ 'is-done': stepperSteps[i + 1]?.done || stepperSteps[i + 1]?.active }"
+          )
 
       v-window.flex-grow-1(v-model="phase")
         v-window-item(value="primer")
           .d-flex.flex-column.align-center.pa-6
-            .hero-wrapper.mb-6
+            .hero-wrapper.mb-4
               KanjiSvgViewer(:char="currentItem.char" mode="hero")
-            .text-h4.font-weight-bold.text-white.mb-2 {{ currentItem.meaning }}
+
-            .text-body-1.text-grey.text-center.mb-8(
+            .text-caption.text-grey.text-uppercase.tracking-wide.mb-1
-              v-if="currentItem.mnemonic") "{{ currentItem.mnemonic }}"
+              ScrambleText(:text="$t('lesson.sectionMeaning')")
-            .radical-section(v-if="currentItem.radicals?.length")
+            .text-h4.font-weight-bold.text-white.mb-4 {{ currentItem.meaning }}
+
+            .mnemonic-box.pa-4.rounded-lg.mb-5(v-if="currentItem.mnemonic")
+              .text-caption.text-grey.text-uppercase.tracking-wide.mb-2.font-weight-bold
+                v-icon.mr-1(size="14" color="amber") mdi-lightbulb-outline
+                ScrambleText(:text="$t('lesson.sectionMnemonic')")
+              .text-body-2.text-grey-lighten-1.font-italic "{{ currentItem.mnemonic }}"
+
+            .radical-section.mb-5(v-if="currentItem.radicals?.length")
               .text-caption.text-grey-darken-1.text-uppercase.mb-3.font-weight-bold
-                |{{ $t('lesson.components') }}
+                ScrambleText(:text="$t('lesson.components')")
               .d-flex.flex-wrap.gap-3.justify-center
                 v-sheet.radical-chip(
                   v-for="rad in currentItem.radicals" :key="rad.meaning")
@@ -38,25 +55,50 @@
                       img(v-if="rad.image" :src="rad.image")
                       span.text-h6.font-weight-bold.text-white(v-else) {{ rad.char }}
                     .text-caption.text-grey-lighten-1 {{ rad.meaning }}
+
+            .text-caption.text-grey.text-uppercase.tracking-wide.mb-3.font-weight-bold.text-center(
+              v-if="(currentItem.onyomi && currentItem.onyomi.length > 0) || (currentItem.kunyomi && currentItem.kunyomi.length > 0)"
+            )
+              ScrambleText(:text="$t('lesson.sectionReadings')")
             .readings-grid(v-if="(currentItem.onyomi && currentItem.onyomi.length > 0) || (currentItem.kunyomi && currentItem.kunyomi.length > 0)")
               .reading-box(v-if="currentItem.onyomi && currentItem.onyomi.length > 0")
-                .label {{ $t('collection.onyomi') }}
+                .label
+                  ScrambleText(:text="$t('collection.onyomi')")
                 .val.text-cyan-lighten-3 {{ currentItem.onyomi.join(', ') }}
               .reading-box(v-if="currentItem.kunyomi && currentItem.kunyomi.length > 0")
-                .label {{ $t('collection.kunyomi') }}
+                .label
+                  ScrambleText(:text="$t('collection.kunyomi')")
                 .val.text-pink-lighten-3 {{ currentItem.kunyomi.join(', ') }}
 
         v-window-item(value="demo")
           .d-flex.flex-column.align-center.justify-center.h-100.pa-6
-            .text-subtitle-1.text-grey.mb-6 {{ $t('lesson.observe') }}
+            .text-subtitle-1.text-grey.mb-6
+              ScrambleText(:text="$t('lesson.observe')")
             .canvas-wrapper.lesson-canvas-wrapper
               KanjiSvgViewer(ref="demoViewer" :char="currentItem.char" mode="animate")
+            v-btn.mt-4(
+              variant="text"
+              color="cyan"
+              prepend-icon="mdi-replay"
+              size="small"
+              @click="replayDemo"
+            )
+              ScrambleText(:text="$t('lesson.replay')")
 
         v-window-item(value="drawing")
           .d-flex.flex-column.align-center.justify-center.h-100.pa-6
-            .text-subtitle-1.text-grey.mb-6
+            .text-subtitle-1.text-grey.mb-2
-              span(v-if="subPhase === 'guided'") {{ $t('lesson.trace') }}
+              span(v-if="subPhase === 'guided'")
-              span(v-else) Draw ({{ practiceCount }}/3)
+                ScrambleText(:text="$t('lesson.trace')")
+              span(v-else)
+                ScrambleText(:text="$t('lesson.drawStep', { n: Math.min(practiceCount + 1, practiceTarget), total: practiceTarget })")
+
+            .practice-dots.mb-4(v-if="subPhase === 'practice'")
+              .practice-dot(
+                v-for="i in practiceTarget"
+                :key="i"
+                :class="{ 'is-filled': i <= practiceCount }"
+              )
 
             .transition-opacity(
               :style="{ opacity: canvasOpacity }"
@@ -76,31 +118,51 @@
           v-if="phase === 'primer'"
           @click="phase = 'demo'"
           color="cyan" rounded="pill" size="large" block
-        ) {{ $t('lesson.understand') }}
+        )
+          ScrambleText(:text="$t('lesson.understand')")
         v-btn.action-btn(
           v-if="phase === 'demo'"
           @click="startDrawing"
           color="cyan" rounded="pill" size="large" block
-        ) {{ $t('lesson.ready') }}
+        )
+          ScrambleText(:text="$t('lesson.ready')")
         .d-flex.justify-center.gap-4.mt-2(v-if="phase === 'drawing' && subPhase === 'practice'")
           v-btn(
            variant="text" color="amber" @click="useHint"
-          ) {{ $t('lesson.hintAction') }}
+          )
-          v-btn(variant="text" color="grey" @click="phase='demo'") {{ $t('lesson.watchAgain') }}
+            ScrambleText(:text="$t('lesson.hintAction')")
+          v-btn(variant="text" color="grey" @click="phase='demo'")
+            ScrambleText(:text="$t('lesson.watchAgain')")
 
-    v-card.text-center.pa-8.lesson-card(
+    v-card.pa-8.lesson-card(
       v-else
     )
-      v-icon.mb-6(size="80" color="purple-accent-2") mdi-check-decagram
+      .d-flex.flex-column.align-center.mb-6
-      .text-h4.font-weight-bold.text-white.mb-2 {{ $t('lesson.completeTitle') }}
+        v-icon.mb-4(size="80" color="purple-accent-2") mdi-check-decagram
-      .text-body-1.text-grey.mb-8 {{ $t('lesson.learned', { n: sessionDone }) }}
+        .text-h4.font-weight-bold.text-white.mb-2
+          ScrambleText(:text="$t('lesson.completeTitle')")
+        .text-body-1.text-grey.mb-2
+          ScrambleText(:text="$t('lesson.learned', { n: sessionDone })")
+
+      .text-caption.text-grey.text-uppercase.tracking-wide.mb-3.text-left.w-100.font-weight-bold
+        ScrambleText(:text="$t('lesson.learnedKanji')")
+
+      .lesson-summary-grid.w-100.mb-6
+        .lesson-summary-item(
+          v-for="item in learnedItems"
+          :key="item.char"
+        )
+          .lesson-summary-char {{ item.char }}
+          .lesson-summary-meaning.text-grey {{ item.meaning }}
+
       v-btn.glow-btn.text-black.font-weight-bold(
         to="/"
         block
         color="cyan"
         height="50"
         rounded="pill"
-      ) {{ $t('lesson.backToDashboard') }}
+      )
+        ScrambleText(:text="$t('lesson.backToDashboard')")
 
 </template>
 
@@ -115,6 +177,7 @@ import { useRoute } from 'vue-router';
 import { useAppStore } from '@/stores/appStore';
 import KanjiCanvas from '@/components/kanji/KanjiCanvas.vue';
 import KanjiSvgViewer from '@/components/kanji/KanjiSvgViewer.vue';
+import { SoundManager } from '@/utils/SoundManager';
 
 const { t } = useI18n();
 const store = useAppStore();
@@ -123,29 +186,49 @@ const currentItem = ref(null);
 const phase = ref('primer');
 const subPhase = ref('guided');
 const practiceCount = ref(0);
+const practiceTarget = 2;
 const sessionDone = ref(0);
 const sessionTotal = ref(0);
 const canvasOpacity = ref(1);
 const loading = ref(true);
+const learnedItems = ref([]);
 
 const canvas = ref(null);
 const demoViewer = ref(null);
 
-const phaseLabel = computed(() => {
+const phaseIndex = computed(() => {
-  if (phase.value === 'primer') return t('lesson.phasePrimer');
+  if (phase.value === 'primer') return 0;
-  if (phase.value === 'demo') return t('lesson.phaseDemo');
+  if (phase.value === 'demo') return 1;
-  return subPhase.value === 'guided' ? t('lesson.phaseGuided') : t('lesson.phasePractice');
+  if (phase.value === 'drawing' && subPhase.value === 'guided') return 2;
+  return 3;
 });
 
-const phaseColor = computed(() => (phase.value === 'primer' ? 'blue' : 'purple'));
+const stepperSteps = computed(() => {
+  const steps = [
+    { key: 'primer', label: t('lesson.phasePrimer') },
+    { key: 'demo', label: t('lesson.phaseDemo') },
+    { key: 'guided', label: t('lesson.phaseGuided') },
+    { key: 'practice', label: t('lesson.phasePractice') },
+  ];
+  return steps.map((s, i) => ({
+    ...s,
+    active: i === phaseIndex.value,
+    done: i < phaseIndex.value,
+  }));
+});
 
 watch(phase, (val) => {
   if (val === 'demo') nextTick(() => demoViewer.value?.playAnimation());
 });
 
+function replayDemo() {
+  demoViewer.value?.playAnimation();
+}
+
 function loadNext() {
   if (store.lessonQueue.length === 0) {
     currentItem.value = null;
+    if (sessionDone.value > 0) SoundManager.playSessionComplete();
     return;
   }
   [currentItem.value] = store.lessonQueue;
@@ -175,7 +258,7 @@ async function handleDrawComplete() {
   } else {
     practiceCount.value += 1;
 
-    if (practiceCount.value < 3) {
+    if (practiceCount.value < practiceTarget) {
       canvasOpacity.value = 0;
       await new Promise((r) => { setTimeout(r, 300); });
       canvas.value?.reset();
@@ -184,9 +267,18 @@ async function handleDrawComplete() {
       const isRedo = !!route.query.subjectId;
 
       if (!isRedo) {
-        await store.submitLesson(currentItem.value.wkSubjectId);
+        try {
+          await store.submitLesson(currentItem.value.wkSubjectId);
+        } catch (e) {
+          console.error('Failed to submit lesson:', e);
+        }
       }
 
+      learnedItems.value.push({
+        char: currentItem.value.char,
+        meaning: currentItem.value.meaning,
+      });
+
       sessionDone.value += 1;
       store.lessonQueue.shift();
       loadNext();
@@ -195,13 +287,15 @@ async function handleDrawComplete() {
 }
 
 function handleMistake() {
-  if (subPhase.value === 'practice') practiceCount.value = 0;
+  if (subPhase.value === 'practice') {
+    practiceCount.value = Math.max(0, practiceCount.value - 1);
+  }
 }
 
 function useHint() {
   canvas.value?.showHint();
   if (subPhase.value === 'practice') {
-    practiceCount.value = 0;
+    practiceCount.value = Math.max(0, practiceCount.value - 1);
   }
 }
 

client/src/views/Review.vue

@@ -3,7 +3,8 @@
     v-fade-transition(mode="out-in")
       .d-flex.flex-column.justify-center.align-center.fill-height(v-if="loading")
         v-progress-circular(indeterminate color="primary" size="64")
-        .text-body-1.text-grey.mt-4 {{ $t('review.loading') }}
+        .text-body-1.text-grey.mt-4
+          ScrambleText(:text="$t('review.loading')")
 
       v-card.pa-6.rounded-xl.d-flex.flex-column.align-center.review-card(
         v-else-if="currentItem"
@@ -23,23 +24,27 @@
             size="small"
             :color="getSRSColor(currentItem.srsLevel)"
             variant="flat"
-          ) {{ $t('review.level') }} {{ currentItem.srsLevel }}
+          )
+            ScrambleText(:text="$t('review.level') + ' ' + currentItem.srsLevel")
 
         .text-center.mb-6
           .text-caption.text-grey.text-uppercase.tracking-wide.mb-1
-            | {{ $t('review.meaning') }}
+            ScrambleText(:text="$t('review.meaning')")
           .text-h3.font-weight-bold.text-white.text-shadow.mb-4
             | {{ currentItem.meaning }}
           .readings-grid(v-if="(currentItem.onyomi && currentItem.onyomi.length > 0) || (currentItem.kunyomi && currentItem.kunyomi.length > 0)")
             .reading-box.reading-box--small(v-if="currentItem.onyomi && currentItem.onyomi.length > 0")
-              .label {{ $t('collection.onyomi') }}
+              .label
+                ScrambleText(:text="$t('collection.onyomi')")
               .val.text-cyan-lighten-3 {{ currentItem.onyomi.join(', ') }}
             .reading-box.reading-box--small(v-if="currentItem.kunyomi && currentItem.kunyomi.length > 0")
-              .label {{ $t('collection.kunyomi') }}
+              .label
+                ScrambleText(:text="$t('collection.kunyomi')")
               .val.text-pink-lighten-3 {{ currentItem.kunyomi.join(', ') }}
 
         .review-canvas-area
           KanjiCanvas(
+            :key="canvasKey"
             ref="kanjiCanvasRef"
             :char="currentItem.char"
             @complete="handleComplete"
@@ -64,18 +69,30 @@
             size="small"
             :disabled="showNext"
             @click="triggerHint"
-          ) {{ $t('review.showHint') }}
+          )
+            ScrambleText(:text="$t('review.showHint')")
 
-        v-sheet.d-flex.align-center.justify-center(
+        v-sheet.d-flex.flex-column.align-center.justify-center(
           width="100%"
-          height="48"
+          min-height="80"
           color="transparent"
         )
           transition(name="fade-slide" mode="out-in")
             .status-text.text-h6.font-weight-bold(
               :key="statusCode"
               :class="getStatusClass(statusCode)"
-            ) {{ $t('review.' + statusCode) }}
+            )
+              ScrambleText(:text="$t('review.' + statusCode)")
+
+          transition(name="scale")
+            v-chip.mt-2.font-weight-bold.elevation-2(
+              v-if="showNext && rankChange"
+              :color="rankChange.type === 'up' ? 'teal-accent-4' : 'red-darken-1'"
+              variant="flat"
+              size="small"
+            )
+              v-icon(start size="14") {{ rankChange.type === 'up' ? 'mdi-arrow-up-thick' : 'mdi-arrow-down-thick' }}
+              | Level {{ currentItem.srsLevel }} → {{ rankChange.level }}
 
         v-progress-linear.mt-4.progress-bar(
           v-model="progressPercent"
@@ -84,23 +101,62 @@
           rounded
         )
 
-      v-card.pa-8.rounded-xl.elevation-10.text-center.review-card(
+      v-card.pa-8.rounded-xl.elevation-10.review-card(
         v-else-if="sessionTotal > 0 && store.queue.length === 0"
       )
-        .mb-6
+        .d-flex.flex-column.align-center.mb-6
           v-avatar(color="rgba(0, 206, 201, 0.1)" size="80")
             v-icon(size="40" color="primary") mdi-trophy
 
-        .text-h4.font-weight-bold.mb-2 {{ $t('review.sessionComplete') }}
+          .text-h4.font-weight-bold.mt-4.mb-2
-        .text-body-1.text-grey.mb-8 {{ $t('review.levelup') }}
+            ScrambleText(:text="$t('review.sessionComplete')")
 
-        v-row.mb-6
+        v-row.mb-4
-          v-col.border-r.border-subtle(cols="6")
+          v-col.text-center.border-r.border-subtle(cols="6")
             .text-h3.font-weight-bold.text-white {{ accuracy }}%
-            .text-caption.text-grey.text-uppercase.mt-1 {{ $t('stats.accuracy') }}
+            .text-caption.text-grey.text-uppercase.mt-1
-          v-col(cols="6")
+              ScrambleText(:text="$t('stats.accuracy')")
+          v-col.text-center(cols="6")
             .text-h3.font-weight-bold.text-white {{ sessionCorrect }}
-            .text-caption.text-grey.text-uppercase.mt-1 {{ $t('stats.correct') }}
+            .text-caption.text-grey.text-uppercase.mt-1
+              ScrambleText(:text="$t('stats.correct')")
+
+        .d-flex.justify-center.ga-4.mb-6(v-if="levelUpCount > 0 || levelDownCount > 0")
+          v-chip.font-weight-bold(
+            v-if="levelUpCount > 0"
+            color="teal-accent-4"
+            variant="tonal"
+            size="small"
+            prepend-icon="mdi-arrow-up-thick"
+          )
+            ScrambleText(:text="$t('review.levelsUp', { n: levelUpCount })")
+          v-chip.font-weight-bold(
+            v-if="levelDownCount > 0"
+            color="red-darken-1"
+            variant="tonal"
+            size="small"
+            prepend-icon="mdi-arrow-down-thick"
+          )
+            ScrambleText(:text="$t('review.levelsDown', { n: levelDownCount })")
+
+        .text-caption.text-grey.text-uppercase.tracking-wide.mb-3.text-left.w-100
+          ScrambleText(:text="$t('review.results')")
+
+        .result-list.w-100.mb-6
+          .result-item(
+            v-for="(r, i) in sessionResults"
+            :key="i"
+          )
+            .result-char {{ r.char }}
+            .result-meaning.text-grey {{ r.meaning }}
+            v-spacer
+            v-chip.font-weight-bold.mr-2(
+              :color="r.success ? 'teal-accent-4' : 'red-darken-1'"
+              variant="tonal"
+              size="x-small"
+            )
+              v-icon(start size="12") {{ r.success ? 'mdi-check' : 'mdi-close' }}
+              | {{ r.oldLevel }} → {{ r.newLevel }}
 
         v-btn.text-black.font-weight-bold.glow-btn(
           to="/"
@@ -108,17 +164,21 @@
           color="primary"
           height="50"
           rounded="lg"
-        ) {{ $t('review.back') }}
+        )
+          ScrambleText(:text="$t('review.back')")
 
       .text-center(v-else)
         v-icon.mb-4(size="64" color="grey-darken-2") mdi-check-circle-outline
-        .text-h4.mb-2.text-white {{ $t('review.caughtUp') }}
+        .text-h4.mb-2.text-white
-        .text-grey.mb-6 {{ $t('review.noReviews') }}
+          ScrambleText(:text="$t('review.caughtUp')")
+        .text-grey.mb-6
+          ScrambleText(:text="$t('review.noReviews')")
         v-btn.font-weight-bold(
           to="/"
           color="primary"
           variant="tonal"
-        ) {{ $t('review.viewCollection') }}
+        )
+          ScrambleText(:text="$t('review.viewCollection')")
 </template>
 
 <script setup>
@@ -126,13 +186,13 @@
 import {
   ref, onMounted, computed, watch,
 } from 'vue';
-import { useRoute, useRouter } from 'vue-router';
+import { useRoute } from 'vue-router';
 import { useAppStore } from '@/stores/appStore';
 import KanjiCanvas from '@/components/kanji/KanjiCanvas.vue';
+import { SoundManager } from '@/utils/SoundManager';
 
 const store = useAppStore();
 const route = useRoute();
-const router = useRouter();
 
 const currentItem = ref(null);
 const statusCode = ref('draw');
@@ -144,6 +204,7 @@ const loading = ref(true);
 const sessionTotal = ref(0);
 const sessionDone = ref(0);
 const sessionCorrect = ref(0);
+const sessionResults = ref([]);
 
 const accuracy = computed(() => {
   if (sessionDone.value === 0) return 100;
@@ -155,19 +216,49 @@ const progressPercent = computed(() => {
   return (sessionDone.value / sessionTotal.value) * 100;
 });
 
+const levelUpCount = computed(() => sessionResults.value.filter((r) => r.success).length);
+const levelDownCount = computed(() => sessionResults.value.filter((r) => !r.success).length);
+
+const submittedItems = ref(new Set());
+const canvasKey = ref(0);
+
 function loadNext() {
   if (store.queue.length === 0) {
     currentItem.value = null;
+    if (sessionTotal.value > 0) SoundManager.playSessionComplete();
     return;
   }
-  const idx = Math.floor(Math.random() * store.queue.length);
+
+  let idx = Math.floor(Math.random() * store.queue.length);
+
+  if (store.queue.length > 1
+    && currentItem.value
+    && store.queue[idx]._id === currentItem.value._id
+  ) idx = (idx + 1) % store.queue.length;
+
   currentItem.value = store.queue[idx];
 
   statusCode.value = 'draw';
   showNext.value = false;
   isFailure.value = false;
+  canvasKey.value += 1;
 }
 
+const rankChange = computed(() => {
+  if (!currentItem.value || !showNext.value) return null;
+
+  if (submittedItems.value.has(currentItem.value._id)) return null;
+
+  const current = currentItem.value.srsLevel;
+
+  if (!isFailure.value) {
+    if (current >= 10) return null;
+    return { type: 'up', level: current + 1 };
+  }
+  if (current <= 1) return null;
+  return { type: 'down', level: current - 1 };
+});
+
 onMounted(async () => {
   loading.value = true;
   const mode = route.query.mode || 'shuffled';
@@ -185,6 +276,8 @@ async function resetSession() {
   sessionDone.value = 0;
   sessionCorrect.value = 0;
   sessionTotal.value = 0;
+  sessionResults.value = [];
+  submittedItems.value.clear();
   currentItem.value = null;
   const mode = route.query.mode || 'shuffled';
   await store.fetchQueue(mode);
@@ -223,31 +316,42 @@ function handleComplete() {
 async function next() {
   if (!currentItem.value) return;
 
-  await store.submitReview(currentItem.value.wkSubjectId, !isFailure.value);
+  const itemId = currentItem.value._id;
+  const isFirstAttempt = !submittedItems.value.has(itemId);
 
-  sessionDone.value += 1;
+  if (isFirstAttempt) {
-  if (!isFailure.value) sessionCorrect.value += 1;
+    const oldLevel = currentItem.value.srsLevel;
-  // eslint-disable-next-line no-underscore-dangle
+    const result = await store.submitReview(currentItem.value.wkSubjectId, !isFailure.value);
-  const index = store.queue.findIndex((i) => i._id === currentItem.value._id);
+    submittedItems.value.add(itemId);
-  if (index !== -1) {
+
-    store.queue.splice(index, 1);
+    const newLevel = result?.srsLevel ?? oldLevel;
+    sessionResults.value.push({
+      char: currentItem.value.char,
+      meaning: currentItem.value.meaning,
+      success: !isFailure.value,
+      oldLevel,
+      newLevel,
+    });
+
+    if (!isFailure.value) {
+      sessionCorrect.value += 1;
+    }
+  }
+
+  if (!isFailure.value) {
+    sessionDone.value += 1;
+    const index = store.queue.findIndex((i) => i._id === itemId);
+    if (index !== -1) {
+      store.queue.splice(index, 1);
+    }
   }
 
   loadNext();
 }
-
-function redoLesson() {
-  if (!currentItem.value) return;
-  router.push({
-    path: '/lesson',
-    query: { subjectId: currentItem.value.wkSubjectId },
-    state: { item: JSON.parse(JSON.stringify(currentItem.value)) },
-  });
-}
-
 const getSRSColor = (lvl) => {
   const colors = {
     1: '#ff7675', 2: '#fdcb6e', 3: '#55efc4', 4: '#0984e3', 5: '#a29bfe', 6: '#6c5ce7',
+    7: '#00cec9', 8: '#fd79a8', 9: '#e84393', 10: '#ffd700',
   };
   return colors[lvl] || 'grey';
 };
@@ -262,7 +366,40 @@ const getStatusClass = (status) => {
 </script>
 
 <style lang="scss" scoped>
+@use '@/styles/abstracts' as *;
+
 .review-view-container {
   min-height: 100%;
 }
+
+.result-list {
+  max-height: 16rem;
+  overflow-y: auto;
+  @include scrollbar;
+  border-radius: $radius-md;
+  background: $bg-glass-subtle;
+}
+
+.result-item {
+  display: flex;
+  align-items: center;
+  padding: $spacing-sm $spacing-md;
+  border-bottom: $border-width-sm solid $color-border;
+
+  &:last-child {
+    border-bottom: none;
+  }
+}
+
+.result-char {
+  font-size: $font-lg;
+  font-weight: $weight-bold;
+  min-width: 2.5rem;
+  text-align: center;
+}
+
+.result-meaning {
+  font-size: $font-sm;
+  margin-left: $spacing-sm;
+}
 </style>