html5添加视频为背景自动播放
<video src="demo.mp4"type="video/mp4" autoplay="autoplay" loop="loop" muted="muted" height="100%" width="100%"></video>
<video src="demo.mp4"type="video/mp4" autoplay="autoplay" loop="loop" muted="muted" height="100%" width="100%"></video>