<style>
.video-container {
position: relative;
padding-bottom: 56.25%; /* 16:9 aspect ratio */
height: 0;
overflow: hidden;
max-width: 100%;
}
.video-container iframe {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}
</style>

<div class="video-container">
<iframe
src="https://www.youtube.com/embed/Kpj6exrv8q4"
title="YouTube video player"
frameborder="0"
allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share"
allowfullscreen>
</iframe>
</div>