1. iOS自动切歌问题（2处）：

- isNearEnd：阈值 0.15s → 0.5s
    - updateTime：移除 iOS 限制
  2. 时长显示负值问题（2处）：
    - formatTime：增加异常值保护
    - resolveDurationSeconds：防止返回负数

index.html

@@ -159,7 +159,8 @@
 
         // --- Utility Functions ---
         const formatTime = (seconds) => {
-            if (!seconds) return "0:00";
+            // 增加保护：处理负数、Infinity、NaN等异常值
+            if (!Number.isFinite(seconds) || seconds < 0) return "0:00";
             const mins = Math.floor(seconds / 60);
             const secs = Math.floor(seconds % 60);
             return `${mins}:${secs < 10 ? '0' : ''}${secs}`;
@@ -232,11 +233,14 @@
                 if (audio.seekable && audio.seekable.length) {
                     try {
                         const end = audio.seekable.end(audio.seekable.length - 1);
+                        // 增加负数检查：iOS锁屏时可能返回负数
                         if (Number.isFinite(end) && end > 0) return end;
                     } catch (e) {}
                 }
             }
-            return getSongDurationSeconds(song);
+            const fallbackDuration = getSongDurationSeconds(song);
+            // 再次确保不会返回负数或异常值
+            return Number.isFinite(fallbackDuration) && fallbackDuration > 0 ? fallbackDuration : 0;
         };
 
         // --- ID Normalization ---
@@ -1231,14 +1235,16 @@
                 const isNearEnd = () => {
                     const durationSeconds = resolveDurationSeconds(audio, currentSongRef.current);
                     if (!Number.isFinite(durationSeconds) || durationSeconds <= 0) return false;
-                    const threshold = IS_IOS ? 0.15 : 0.35;
+                    // iOS锁屏时timeupdate频率降低，需要更大的提前量
+                    const threshold = IS_IOS ? 0.5 : 0.35;
                     return audio.currentTime >= durationSeconds - threshold;
                 };
 
                 const updateTime = () => {
                     setCurrentTime(audio.currentTime);
                     if (autoAdvanceLockRef.current) return;
-                    if (!IS_IOS && isNearEnd()) triggerAutoNext();
+                    // 移除iOS限制：所有平台都使用timeupdate检查，解决iOS锁屏时ended事件不触发的问题
+                    if (isNearEnd()) triggerAutoNext();
                 };
                 const updateDuration = () => setDuration(resolveDurationSeconds(audio, currentSongRef.current));
                 const onEnded = () => triggerAutoNext();