video-embed.css

/* Nathan Lam
   June 2, 2017

   Add this css for responsive embedded videos in your .css file. */

.embed-container {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  max-width: 100%;
}

.embed-container iframe, .embed-container object, .embed-container embed {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}