refactor: 優化例句口說功能設計與用戶體驗

## VoiceRecorder 組件改進
- 添加自定義說明文字 prop (instructionText)
- 調整布局順序：圖片 → 說明 → 例句
- 統一圖片容器樣式與其他模式一致

## 例句口說頁面優化
- 移除重複的例句和圖片顯示
- 簡化錄音完成回饋區域
- 移除不必要的目標單字和發音顯示
- 調整回饋訊息為分行顯示，提升可讀性
- 實現滿版寬度布局

## 用戶體驗改進
- 消除重複內容，介面更簡潔
- 統一設計語言，視覺一致性更好
- 優化訊息層次，重點更突出

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/app/learn/page.tsx

@@ -937,42 +937,12 @@ export default function LearnPage() {
                 </span>
               </div>
 
-              {/* Example Image */}
-              {currentCard.exampleImage && (
-                <div className="mb-6">
-                  <div className="bg-gray-50 rounded-lg p-4">
-                    <img
-                      src={currentCard.exampleImage}
-                      alt="Example illustration"
-                      className="w-full max-w-md mx-auto rounded-lg cursor-pointer"
-                      onClick={() => setModalImage(currentCard.exampleImage)}
-                    />
-                  </div>
-                </div>
-              )}
-
-              <p className="text-lg text-gray-700 mb-2 text-left">
-                請看例句圖片並大聲說出完整的例句：
-              </p>
-
-              <div className="space-y-4 mb-8">
-                {/* Example Sentence */}
-                <div className="bg-gray-50 rounded-lg p-4">
-                  <h3 className="font-semibold text-gray-900 mb-2 text-left">例句</h3>
-                  <div className="relative">
-                    <p className="text-gray-700 italic mb-2 text-left pr-12">"{currentCard.example}"</p>
-                    <div className="absolute bottom-0 right-0">
-                      <AudioPlayer text={currentCard.example} />
-                    </div>
-                  </div>
-                  <p className="text-gray-600 text-sm text-left">"{currentCard.exampleTranslation}"</p>
-                </div>
-
-              </div>
-
-              <div className="max-w-md mx-auto">
+              <div className="w-full">
                 <VoiceRecorder
                   targetText={currentCard.example}
+                  targetTranslation={currentCard.exampleTranslation}
+                  exampleImage={currentCard.exampleImage}
+                  instructionText="請看例句圖片並大聲說出完整的例句："
                   onRecordingComplete={() => {
                     // 簡化處理：直接顯示結果
                     handleSpeakingAnswer(currentCard.example)
@@ -981,21 +951,13 @@ export default function LearnPage() {
               </div>
 
               {showResult && (
-                <div className="mt-6 p-4 rounded-lg bg-blue-50 border border-blue-200 max-w-md mx-auto">
-                  <p className="text-blue-700 text-center">
-                    錄音完成！系統正在評估你的發音...
+                <div className="mt-6 p-6 rounded-lg bg-blue-50 border border-blue-200 w-full">
+                  <p className="text-blue-700 text-left text-xl font-semibold mb-2">
+                    錄音完成！
+                  </p>
+                  <p className="text-gray-600 text-left">
+                    系統正在評估你的發音...
                   </p>
-                  <div className="mt-4 text-center">
-                    <p className="text-gray-700">
-                      目標單字：<strong>{currentCard.word}</strong>
-                    </p>
-                    <p className="text-gray-600 mt-1">
-                      發音：{currentCard.pronunciation}
-                    </p>
-                    <div className="mt-2">
-                      <AudioPlayer text={currentCard.word} />
-                    </div>
-                  </div>
                 </div>
               )}
             </div>

frontend/components/VoiceRecorder.tsx

@@ -24,6 +24,7 @@ export interface VoiceRecorderProps {
   targetText: string;
   targetTranslation?: string;
   exampleImage?: string;
+  instructionText?: string;
   onScoreReceived?: (score: PronunciationScore) => void;
   onRecordingComplete?: (audioBlob: Blob) => void;
   maxDuration?: number;
@@ -35,6 +36,7 @@ export default function VoiceRecorder({
   targetText,
   targetTranslation,
   exampleImage,
+  instructionText,
   onScoreReceived,
   onRecordingComplete,
   maxDuration = 30, // 30 seconds default
@@ -245,13 +247,23 @@ export default function VoiceRecorder({
       {/* Example Image */}
       {exampleImage && (
         <div className="mb-4">
-          <img
-            src={exampleImage}
-            alt="Example context"
-            className="w-full rounded-lg shadow-md cursor-pointer hover:shadow-lg transition-shadow"
-            style={{ maxHeight: '400px', objectFit: 'contain' }}
-          />
-          <div className="text-xs text-gray-500 mt-2 text-center">點擊圖片可放大查看</div>
+          <div className="bg-gray-50 rounded-lg p-4">
+            <img
+              src={exampleImage}
+              alt="Example context"
+              className="w-full max-w-md mx-auto rounded-lg cursor-pointer"
+              style={{ maxHeight: '400px', objectFit: 'contain' }}
+            />
+          </div>
+        </div>
+      )}
+
+      {/* Instruction Text */}
+      {instructionText && (
+        <div className="mb-6">
+          <p className="text-lg text-gray-700 text-left">
+            {instructionText}
+          </p>
         </div>
       )}