JSFiddle - React, Tailwind, and code Playground

HTML

<div class="video-container">
       <iframe src="//www.youtube.com/embed/k_d5jWvBirU?wmode=opaque&amp;rel=0&amp;showinfo=0&amp;modestbranding=1&amp;controls=2&amp;autohide=1&amp;enablejsapi=1" frameborder="0" allowfullscreen="" id="widget2"></iframe>
    </div>

CSS

.video-container {
      position: relative;
      width: 100%;
      height: 0;
      padding-bottom: 56.25%;
      background: #000;
    }
    .video-container iframe {
      position: absolute;
      top: 0;
      right: 0;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 100%;
    }