.embed-container {
  max-width: 550px;
}
.video-wrapper {
  position: relative;
  padding-bottom: 56.25%; /* 16:9 */
  height: 0;
  min-width: 300px;
  min-height: calc(300px * 0.5625);
}
.video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}