<div class="video">
	<iframe width="560" height="315" src="https://www.youtube.com/embed/rhxQoDlt2AU" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
</div>

.video{
	position: relative;
	padding-top: calc(9 / 16 * 100%);
}
iframe{
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
}