绝对定位一个div

#zvnoticebox{z-index:100000;width:332px;position:fixed;bottom:0;right:2px;_position:absolute;_top: expression(eval(document.documentElement.scrollTop+document.documentElement.clientHeight-this.offsetHeight-(parseInt(this.currentStyle.marginTop,10)||0)-(parseInt(this.currentStyle.marginBottom,10)||0)));}