diff --git a/src/app/words/word-day.tsx b/src/app/words/word-day.tsx
index b0a83cb..fa1633d 100644
--- a/src/app/words/word-day.tsx
+++ b/src/app/words/word-day.tsx
@@ -29,7 +29,12 @@ function RecordBtn({ day, word }: { day: number; word: string }) {
   const start = async () => {
     try {
       const stream = await navigator.mediaDevices.getUserMedia({ audio: true });
-      const mr = new MediaRecorder(stream);
+      // 优先选 Safari/Chrome 都能播放的 mp4,家长端 iOS 才能回放
+      const mime =
+        ["audio/mp4", "audio/mp4;codecs=mp4a.40.2", "audio/webm;codecs=opus", "audio/webm"].find(
+          (t) => typeof MediaRecorder !== "undefined" && MediaRecorder.isTypeSupported(t),
+        ) || "";
+      const mr = new MediaRecorder(stream, mime ? { mimeType: mime } : undefined);
       const chunks: Blob[] = [];
       mr.ondataavailable = (e) => chunks.push(e.data);
       mr.onstop = async () => {