頂部出現,然後慢慢消失

<div id="divName" style="width:920px;height:0px;overflow:hidden;background:#ffffff; margin:0px auto" οnclick="closead()">

</div>

<!---五一勞動節-->
<div id="ss" style="display:none">

<img alt="五一勞動節快樂" src="/image/wuyi01.jpg" />

</div>

<script type="text/javascript">
    setTimeout("dd()",1000);
   
   
    function dd()
    {
        document.getElementById('divName').innerHTML=document.getElementById('ss').innerHTML;
        document.getElementById('ss').innerHTML="";
        document.getElementById('divName').style.height="250px";
        setTimeout("closead()",3000);
    }
</script>

<script type="text/javascript">

 function closead()
{
    //divName.style.pixelWidth-=6;
    document.getElementById('divName').style.pixelHeight-=6;
 
    if (document.getElementById('divName').style.pixelHeight<=0 )
    {
        clearTimeout(timer);
        //document.getElementById('divName').style.display="none";
    }
    else
        timer=setTimeout("closead()",50);
}
</script>

<!---五一勞動節 結束--->