video铺满div
*{
margin:0; padding:0;
}
html,
body,
#app{
height: 100%;
width: 100%;
min-width: 1300px;
margin: 0;
overflow: hidden;
/*font-family: "Helvetica Neue",Helvetica,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","微软雅黑",Arial,sans-serif;*/
}
.video{
width: 100%;
height: 100%;
object-fit: fill // 重点
}
<div id="app">
<video src="./background.mp4" class="video" autoplay="autoplay" muted="muted" preload loop>
your browser does not support the video tag
</video>
</div>