.embed-responsive {
  position: relative;
  display: block;
  width: 100%;
  padding: 0;
  overflow: hidden;
}
.embed-responsive::before {
    display: block;
    content: "";
}

.embed-responsive .embed-responsive-item,
.embed-responsive iframe,
.embed-responsive embed,
.embed-responsive object,
.embed-responsive video {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}


.embed-responsive-16by9::before {
    padding-top: 56.25%;
}