<link href="//maxcdn.bootstrapcdn.com/font-awesome/4.1.0/css/font-awesome.min.css" rel="stylesheet">

<div class='thetop'></div>
<div class='testheight'>Some exciting content... Scroll down for the button to appear.<br><br>
<i class="fa fa-4x fa-thumbs-up fa-spin"></i>
</div>

<div class='scrolltop'>
    <div class='scroll icon'><i class="fa fa-4x fa-angle-up"></i></div>
</div>