JSFiddle - React, Tailwind, and code Playground

by Oliver

HTML

<div class="bg-video">
  <iframe class="bg-video__iframe" src="https://www.youtube.com/embed/biWk-QLWY7U?controls=0&showinfo=0&rel=0&autoplay=1&loop=1&mute=1" frameborder="0" allowfullscreen></iframe>
</div>

SCSS

* {
  padding: 0;
  margin: 0;
}

:root {
  --video-width: 100vw;
  --video-height: 100vh;
  
  @media (min-aspect-ratio: 16/9) {
    --video-height: 56.25vw;
  }

  @media (max-aspect-ratio: 16/9) {
    --video-width: 177.78vh;
  }
}

.bg-video {
  position: relative;
  overflow: hidden;
  width: 100vw;
  height: 100vh;
}

.bg-video__iframe {
  position: absolute;
  top: 50%;
  left: 50%;
  width: var(--video-width);
  height: var(--video-height);
  transform: translate(-50%, -50%);
}