<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.8/jquery-ui.js"></script>
<link rel="stylesheet" type="text/css" href="style/main.css" />
<title>Drag and drop</title>
<style type="text/css">
.drag{
border : 1px solid black;
width : 100;
height : 100;
z-index : 10;
}
</style>
</head>
<body>
<div id="el-1" class="drag" name="g"></div>
<div id="el-2" class="drag"></div>
<script>
z=0;
$(document).ready(function() {
$("div#el-1").css("background-color", "silver");
$("div#el-2").css("background-color", "grey");
$('.drag').draggable({
start:function(){this.style.zIndex=z++}
});
});
</script>
</body>
</html>