Update index.html

index.html

@@ -909,7 +909,7 @@ document.getElementById('sw-register-btn').addEventListener('click', async () =>
             </div>
             
             <video id="video" muted>
-                <source src="v.mp4" type="video/mp4">
+                <source src="v.mp4" type="video/mp4" allowPictureInPicture>
             </video>
             <div class="video-controls">
                 <div class="progress-container" id="progress-container">
@@ -1129,6 +1129,15 @@ document.addEventListener('DOMContentLoaded', function() {
     video.preservesPitch = true;
     video.mozPreservesPitch = true; // Firefox用
     video.webkitPreservesPitch = true; // 古いWebKit用
+    document.addEventListener('visibilitychange', async () => {
+    if (document.hidden && !document.pictureInPictureElement && !video.paused) {
+      try {
+        await video.requestPictureInPicture();
+      } catch (err) {
+        console.error('PiP起動エラー:', err);
+      }
+    }
+  });
     const videoContainer = document.getElementById('video-container');
     const playPauseBtn = document.getElementById('play-pause-btn');
     const timeDisplay = document.getElementById('time-display');