.embed-container {
position: relative;
padding-bottom: 46.25%; /* 16/9 ratio */
padding-top: 30px; /* IE6 workaround*/
height: 0;
overflow: hidden;
}
.embed-container iframe,
.embed-container object,
.embed-container embed {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}
<div class="embed-container">
<iframe src="http://www.youtube.com/embed/sJWeG5TL14Q" frameborder="0" webkitAllowFullScreen mozallowfullscreen allowfullscreen></iframe>
</div>
Labels: dynamic, embed, responsive design, video, youtube