lesson 12 grammar remaining

docs/.vitepress/theme/components/TTS.vue

@@ -3,7 +3,11 @@
     <span ref="main" :class="class" :lang="lang">
       <slot />
     </span>
-    <audio style="display: none" ref="audio"></audio>
+    <audio
+      style="display: none"
+      ref="audio"
+      @error="playAudioTTSPlugin()"
+    ></audio>
     <span>
       <button type="button" @click="playAudio()" :class="$style.speak">
         🗣️
@@ -80,7 +84,6 @@ async function playAudioTTSPlugin(): Promise<boolean> {
 
 <style module>
 .speak {
-  text-align: center;
-  width: 2em;
+  margin-inline-start: 0.2em;
 }
 </style>