.youtube {
  width: 100%;
  padding: 0;
  box-sizing: border-box;
  display: flex;
  justify-content: center;
}

.youtube .inner {
  width: 70%;
  padding-top: 56.25%;
  position: relative;
  height: 0;
  overflow: hidden;
}

.youtube .inner iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}