fix: include lesson stepper styles in build, restrict scramble to locale changes only

- Lesson stepper CSS was not committed (only in working tree), causing vertical layout in production
- ScrambleText now only animates when locale changes, not on any text prop change (e.g. on/off toggle)

client/src/components/ScrambleText.vue

@@ -4,17 +4,20 @@
 
 <script setup>
 import { ref, watch, onBeforeUnmount } from 'vue';
+import { useI18n } from 'vue-i18n';
 
 const props = defineProps({
   text: { type: String, required: true },
 });
 
+const { locale } = useI18n();
 const displayText = ref(props.text);
 let frameId = null;
+let lastLocale = locale.value;
 
 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
+const DURATION = 400;
+const STEPS_PER_CHAR = 3;
 
 function scrambleTo(newText) {
   if (frameId) cancelAnimationFrame(frameId);
@@ -22,8 +25,6 @@ function scrambleTo(newText) {
   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) => {
@@ -35,15 +36,12 @@ function scrambleTo(newText) {
       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];
@@ -51,7 +49,6 @@ function scrambleTo(newText) {
           result += CHARS[Math.floor(Math.random() * CHARS.length)];
         }
       } else {
-        // Hasn't started yet — show old char or space
         result += i < oldText.length ? oldText[i] : ' ';
       }
     }
@@ -69,8 +66,21 @@ function scrambleTo(newText) {
   frameId = requestAnimationFrame(tick);
 }
 
+// Only scramble when locale changes, otherwise update silently
 watch(() => props.text, (newVal) => {
-  scrambleTo(newVal);
+  if (locale.value !== lastLocale) {
+    lastLocale = locale.value;
+    scrambleTo(newVal);
+  } else {
+    displayText.value = newVal;
+  }
+});
+
+// Also watch locale directly to catch the change
+watch(locale, () => {
+  // The text prop will update right after locale changes,
+  // so we just mark it and let the text watcher handle animation
+  lastLocale = '__pending__';
 });
 
 onBeforeUnmount(() => {

client/src/styles/pages/_lesson.scss

@@ -19,3 +19,151 @@
 .lesson-canvas-wrapper {
 	margin: 0 auto;
 }
+
+// ── Phase Stepper ──────────────────────────────────
+
+.lesson-stepper {
+	display: flex;
+	align-items: flex-start;
+	gap: 0;
+}
+
+.lesson-stepper__step {
+	display: flex;
+	flex-direction: column;
+	align-items: center;
+	gap: 0.25rem;
+	flex-shrink: 0;
+}
+
+.lesson-stepper__dot {
+	width: 1.75rem;
+	height: 1.75rem;
+	border-radius: $radius-circle;
+	display: flex;
+	align-items: center;
+	justify-content: center;
+	font-size: $font-xs;
+	font-weight: $weight-bold;
+	background: $color-surface-light;
+	color: $color-text-grey;
+	border: $border-width-md solid transparent;
+	transition: all $duration-normal $ease-default;
+
+	.is-active & {
+		background: $color-primary;
+		color: $color-text-dark;
+		border-color: $color-primary;
+		box-shadow: $shadow-glow-base;
+	}
+
+	.is-done & {
+		background: $color-success;
+		color: $color-text-white;
+		border-color: $color-success;
+	}
+}
+
+.lesson-stepper__label {
+	font-size: 0.6rem;
+	text-transform: uppercase;
+	letter-spacing: 0.05em;
+	font-weight: $weight-bold;
+	color: $color-text-grey;
+	opacity: $opacity-inactive;
+	transition: opacity $duration-normal $ease-default;
+	white-space: nowrap;
+
+	.is-active & {
+		opacity: $opacity-active;
+		color: $color-primary;
+	}
+
+	.is-done & {
+		opacity: 0.6;
+		color: $color-success;
+	}
+}
+
+.lesson-stepper__line {
+	flex: 1;
+	height: $border-width-md;
+	background: $color-surface-light;
+	border-radius: $radius-pill;
+	transition: background $duration-normal $ease-default;
+	margin: 0.875rem $spacing-xs 0;
+
+	&.is-done {
+		background: $color-success;
+	}
+}
+
+// ── Practice Dots ──────────────────────────────────
+
+.practice-dots {
+	display: flex;
+	gap: $spacing-sm;
+	justify-content: center;
+}
+
+.practice-dot {
+	width: 0.625rem;
+	height: 0.625rem;
+	border-radius: $radius-circle;
+	background: $color-surface-light;
+	transition: all $duration-normal $ease-out-back;
+
+	&.is-filled {
+		background: $color-primary;
+		box-shadow: 0 0 0.5rem $color-primary;
+		transform: scale(1.2);
+	}
+}
+
+// ── Mnemonic Box ───────────────────────────────────
+
+.mnemonic-box {
+	width: 100%;
+	background: $bg-glass-subtle;
+	border: $border-width-sm solid $color-border;
+}
+
+// ── Lesson Summary ─────────────────────────────────
+
+.lesson-summary-grid {
+	display: grid;
+	grid-template-columns: repeat(auto-fill, minmax(5rem, 1fr));
+	gap: $spacing-sm;
+}
+
+.lesson-summary-item {
+	display: flex;
+	flex-direction: column;
+	align-items: center;
+	padding: $spacing-md $spacing-sm;
+	background: $bg-glass-subtle;
+	border-radius: $radius-lg;
+	border: $border-width-sm solid $color-border;
+	transition: border-color $duration-normal $ease-default;
+
+	&:hover {
+		border-color: $color-primary;
+	}
+}
+
+.lesson-summary-char {
+	font-size: $font-xl;
+	font-weight: $weight-bold;
+	margin-bottom: $spacing-xs;
+}
+
+.lesson-summary-meaning {
+	font-size: $font-xs;
+	text-align: center;
+}
+
+// ── Utility ────────────────────────────────────────
+
+.stepper-spacer {
+	width: 2.5rem;
+}