如何:使我的视频背景居中和缩放，而不是改变浏览器的大小？

<div id="video-container">
  <video src="your-video-source.mp4" autoplay loop></video>
</div>

#video-container {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: -1;
  overflow: hidden;
}

#video-container video {
  min-width: 100%;
  min-height: 100%;
  width: auto;
  height: auto;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

window.addEventListener('resize', function() {
  var videoContainer = document.getElementById('video-container');
  var video = videoContainer.querySelector('video');
  var windowWidth = window.innerWidth;
  var windowHeight = window.innerHeight;
  var videoAspectRatio = video.videoWidth / video.videoHeight;
  var windowAspectRatio = windowWidth / windowHeight;

  if (windowAspectRatio > videoAspectRatio) {
    video.style.width = '100%';
    video.style.height = 'auto';
  } else {
    video.style.width = 'auto';
    video.style.height = '100%';
  }
});