div 元素拖拽插件，需要用到两个插件 jquery.event.ue.js jquery.udraggable.js
<script src="js/jquery.event.ue.js" type="text/javascript" charset="utf-8"></script>
<script src="js/jquery.udraggable.js" type="text/javascript" charset="utf-8"></script>
<div id="kefu" class="kefu-link">
<a href="#" class="robot-link">
<img src="images/customer@2x.png" >
<div class="eye-top"></div>
<div class="eye-bottom"></div>
</a>
</div>
<script type="text/javascript">
$('#kefu').udraggable({});
</script>