<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<div class="container section-header">
<h2>Create your snippet's HTML, CSS and Javascript in the editor tabs</h2>
<br/>
<hr class="lines wow zoomIn animated" data-wow-delay="0.3s" style="visibility: visible;-webkit-animation-delay: 0.3s; -moz-animation-delay: 0.3s; animation-delay: 0.3s;">
</div>