<link href="//netdna.bootstrapcdn.com/bootstrap/3.1.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.1.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<div class="container">
<div class="row">
<h2>Mr. M.' full videoCreate your snippet's HTML, CSS and Javascript in the editor tabs</h2>
</div>
</div>
<section class="row">
<div class="span6">
<div class="flex-video widescreen"><iframe src="//www.youtube.com/embed/ac7KhViaVqc" frameborder="0" allowfullscreen=""></iframe></div>
</div>
<div class="span6">
...
</div>
</section>
.flex-video {
position: relative;
padding-top: 25px;
padding-bottom: 67.5%;
height: 0;
margin-bottom: 16px;
overflow: hidden;
}
.flex-video.widescreen { padding-bottom: 57.25%; }
.flex-video.vimeo { padding-top: 0; }
.flex-video iframe,
.flex-video object,
.flex-video embed {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}
@media only screen and (max-device-width: 800px), only screen and (device-width: 1024px) and (device-height: 600px), only screen and (width: 1280px) and (orientation: landscape), only screen and (device-width: 800px), only screen and (max-width: 767px) {
.flex-video { padding-top: 0; }
}