<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/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">
<div class="embed-responsive embed-responsive-4by3">
<iframe class="embed-responsive-item" src="https://www.youtube.com/watch?v=zpOULjyy-n8"></iframe>
</div>
</div>
</div>
