<style>
.youtube {
position: relative;
width: 100%;
padding-top: 56.25%;
}
.youtube iframe {
position: absolute;
top: 0;
right: 0;
width: 100%;
height: 100%;
}
</style>
<div class="youtube">
<iframe width="560" height="315" src="https://www.youtube.com/embed/Cg6mkypdbUQ&quot; title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
</div>