css 漂浮

<style type="text/css">
        body
        {
            background-image: url(text.txt); /*text.txt防抖*/ /* for IE6 */
            background-attachment: fixed;
        }
        #Piao_R
        {
            background-color: #D5D8DE;
            
            text-align: center;
            z-index: 999;
            position: fixed;
            bottom: 0;
            top:200px;
            right: 150px;
            width: 50;
            height: 40px;
            line-height: 40px; /* for IE6 */
            _position: absolute;
            _top: expression(documentElement.scrollTop + documentElement.clientHeight-this.offsetHeight);
            overflow: visible;
        }
    </style>

　　

<div id="Piao_R">
        <a target="_blank" href="http://kefu.emoney.cn/ServiceCentre/Centre/infopage?infoid=107&menuid=2">
        <img id="anzhuang_img" src="content/images/anzhuang1.bmp" /></a>
    </div>