a.button {
 padding: 8px 20px 6px 20px !important;   
}

.embed-responsive-16by9 {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%; /* 16:9 aspect ratio */
  height: 0;
  overflow: hidden;
}

.embed-responsive-16by9 iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}