<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.11/jquery-ui.min.js"></script>
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.11/themes/base/jquery-ui.css">
<div id="content">
<div id="topDiv">
This is top div element.
</div>
<div id="bottomDiv">
This is bottom div element.
</div>
</div>