div.left{float: left;width: 250px;}
div.right{float: right;width: 340px;}
div.zTreeDemoBackground {width:250px;height:362px;text-align:left;}
ul.ztree {margin-top: 0px;border: 1px solid #e0dede;width:220px;height:500px;overflow-y:scroll;overflow-x:auto;}