<iframe class="responsive-video" width="560" height="315" src="https://www.youtube.com/embed/u9ounrieFK0" title="Portal - Glitchless Speedrun - 24:16.76" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
.responsive-video {
  width: 100%;
  height: 100%;
  
  aspect-ratio: 16 / 9;
  object-fit: contain;
}

:root {
	--clr-bg: 220 39% 15%;
  --clr-dark: 220 39% 10%;
  --clr-main: 0 100% 67%;
  --clr-light: 44 100% 88%;
  --clr-bright: 43 100% 65%;
  --clr-link: 199 100% 65%;
  --clr-text-base: 220 39% 95%;
}

// Base Styles
* {
	box-sizing: border-box;
}
body {
	padding: 10px;

	background: hsl(var(--clr-bg));
	font: 400 1rem / 1.5 sans-serif;
}
h3 {
	margin: -20px -20px 15px -20px;
	padding: 20px 20px 10px;

	background: hsl(var(--clr-light));

	color: hsl(var(--clr-dark));
}
p {
	margin: 0;

	color: #efefef;
}

External CSS

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External JavaScript

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