html js dom 的页面浮动滚动

图片说明这是我的代码~~~请大神们指导，，哪里出问题了，运行后没反应

-----------------------html文件--------------------

 <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
    <title>仿163世界杯信息条</title>
    <script type="text/javascript" src="script3.js"></script>
    <style type="text/css">
    #info{
        position: absolute;
        bottom: 0px;
        margin-left: 190px;
        z-index: 1;
    }
    #clo{
        position: absolute;
        right: 5px;
        top: 2px;
        font-size: 12px;
        cursor: pointer;
        z-index: 2;
    }
</style>
</head>

<body>
<div id="main" align="center">
    <div id="info" align="center">
    <span id="clo" onclick="cloinfo()">关闭</span>
    <img src="foot.jpg">
    </div>
<img src="content.jpg">
</div>
</body>
</html>

---------------------------------script文件-------------------------------------------

var ih;
var ch;
function move(){

    ch = document.documentElement.clientHeight;
// 
    ih = document.getElementById("info").offsetHeight;

    document.getElementById("info").style.top = (ch - ih 
        +document.documentElement.scrollTop) +'px';
        // alert(document.getElementById("info").style.top);
}

window.onscroll = move;

function cloinfo(){
    document.getElementById("info").style.display="none";

}

#info选择器去掉bottom: 0px;


        #info {
            position: absolute;
            margin-left: 190px;
            z-index: 1;
        }