/* 播放按钮 */
.play-button {
  position: absolute;
  top: 34%;
  left: 50%;
  transform: translate(-50%, -50%) translateZ(10px);
  background: rgba(255,255,255,0.7);
  border-radius: 50%;
  width: 50px;
  height: 50px;
  display: none;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  color: #000;
  opacity: 0;
  transition: opacity 0.3s, width 0.3s, height 0.3s, background 0.3s;
  z-index: 10;
  box-shadow: 0 4px 8px rgba(0,0,0,0.3);
}
.play-button::before {
  content: '▶';
  opacity: 1;
  position: relative;
  left: 2px;
  top: -1px;
  transition: transform 0.3s, font-size 0.3s, text-shadow 0.3s;
  text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}
.cover-flow li:hover img {
  position: relative;
  z-index: 9;
}
.cover-flow li.centered .play-button {
  opacity: 0.7;
  display: flex;
}
.play-button:hover {
  width: 47px;
  height: 47px;
  background: rgba(255,255,255,0.5);
}
.play-button:hover::before {
  font-size: 26px;
  transform: translate(0px, 0px);
  text-shadow: 0 4px 8px rgba(0,0,0,0.4);
}
/* 视频播放模态 */
.video-player-container {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.9);
  z-index: 20;
  justify-content: center;
  align-items: center;
}
.video-player {
  width: 80%;
  max-height: 80%;
}
.close-player {
  position: absolute;
  top: 60px;
  right: 40px;
  font-size: 30px;
  cursor: pointer;
}
/* Mobile mode: when aspect-ratio > 1:2 (i.e., max-aspect-ratio: 1/2) */
@media (max-aspect-ratio: 1/1) {
  .play-button {
    top: 30%;
  }
}
@media (prefers-color-scheme: light) {
  .video-player-container {
    background: rgba(255,255,255,0.9);
  }
  .play-button {
    background: rgba(0,0,0,0.7);
    color: #fff;
  }
  .play-button::before {
    text-shadow: 0 2px 4px rgba(255,255,255,0.2);
  }
  .play-button:hover {
    background: rgba(0,0,0,0.5);
  }
  .play-button:hover::before {
    text-shadow: 0 4px 8px rgba(255,255,255,0.4);
  }
}