#tbox
{
    width: 47px;
    height: 73px;
    float: right;
    position: fixed;
    _position: absolute;
    _bottom: auto;
    _top: expression(eval(document.documentElement.scrollTop+document.documentElement.clientHeight-this.offsetHeight-(parseInt(this.currentStyle.marginTop, 10)||0)-(parseInt(this.currentStyle.marginBottom, 10)||0)));
    _margin-bottom: 10px;
}
/*解决IE6下不兼容 position:fixed 的问题*/

#gotop
{
    width: 47px;
    height: 47px;
    background: url(img/top01.png) no-repeat;
    position: absolute;
    top: 0px;
    display: none;
    cursor: pointer;
}

#gotop:hover
{
    background: url(img/top02.png) no-repeat;
}