Video, YouTube, Scale, Scalable

<style type="text/css">
.videoWrapper {
	position: relative;
	padding-bottom: 56.25%; /* 16:9 */
	padding-top:5px; height: 0; }
.videoWrapper iframe {
	position: absolute;
	top: 0; left: 0; width: 100%; height: 100%; }
</style>
<div class="videoWrapper">
<iframe width="560" height="349" 
src="http://www.youtube.com/embed/555555555555?rel=0&amp;hd=1" 
frameborder="0" allowfullscreen="allowfullscreen"></iframe>
</div>