video, iframe, responsive, wrapper
.videoWrapper {
position: relative;
padding-bottom: 56.25%; /* 16:9 */
padding-bottom: 75%; /* 420w/315h youtube */
padding-top: 25px;
height: 0;
}
.videoWrapper iframe {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}
// jquery to wrap iframe with wrapper
$('.std iframe').wrap('<div class="videoWrapper" />');