JSFiddle - React, Tailwind, and code Playground

HTML

<div id="video-wrap">
  <video id="video" loop autoplay>
    <source src="http://techslides.com/demos/sample-videos/small.mp4" type="video/mp4">
    Your browser does not support HTML5 video.
  </video>
</div>

CSS

#video-wrap {
  position: fixed;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
}

#video {
  position: absolute;
  top: -9999px;
  bottom: -9999px;
  left: -9999px;
  right: -9999px;
  margin: auto;
  min-width: 100%;
  min-height: 100%;
  width: auto;
  height: auto;
}