<main>
  <video src="https://assets.codepen.io/3/mov_bbb.mp4" muted autoplay loop playsinline controls></video>
</main>
video {
  width: 100%;
  aspect-ratio: 16 / 9;
}

main {
  max-inline-size: 70ch;
  margin-inline: auto;
  min-block-size: 100dvh;
  background: white;
  padding: 1rem;
}
body {
  background: #eee;
  margin: 0;
}
* {
  box-sizing: border-box;
}

External CSS

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External JavaScript

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