.video-responsive {
position: relative;
padding-bottom: 56.25%; /* 16/9 ratio */
padding-top: 30px; /* IE6 workaround*/
height: 0;
overflow: hidden;
}
 
.video-responsive iframe,
.video-responsive object,
.video-responsive embed {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}