Automatically Resize A YouTube Embed To Fit In Another Element

This is how I'm using the basic YouTube embed iframe and wrapping it in a <div> that makes it responsive.

Output From HTML

<div class="example-wrapper">
<iframe 
  width="560" 
  height="315" 
  src="https://www.youtube.com/embed/REPPgPcw4hk" 
  title="YouTube video player" 
  frameborder="0" 
  allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" 
  referrerpolicy="strict-origin-when-cross-origin" 
  allowfullscreen></iframe>
</div>

CSS

.example-wrapper {
  position: relative;
  padding-bottom: 56.25%; /* 16:9 */
  height: 0;
}
.example-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}
~ fin ~

References