<link href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<span class="fa-stack fa-2x has-badge" data-count="2">
<i class="fa fa-circle fa-stack-2x"></i>
<i class="fa fa-bell fa-stack-1x fa-inverse"></i>
</span>
<!-- found at https://codepen.io/johnstuif/pen/pvLgYp -->