把下面的代码加入外观的footer.php文件就可以了

<div class="yunxing">
已运行
<span id="span_dt_dt" style='border:0px solid black' ></span>
<SCRIPT language=javascript>
<!--
//document.write("");
function show_date_time(){
window.setTimeout("show_date_time()", 1000);
BirthDay=new Date("08-08-2011"); //提示：这里的07-31-2009是指建站日期
today=new Date();
timeold=(today.getTime()-BirthDay.getTime());
sectimeold=timeold/1000
secondsold=Math.floor(sectimeold);
msPerDay=24*60*60*1000
e_daysold=timeold/msPerDay
daysold=Math.floor(e_daysold);
e_hrsold=(daysold-e_daysold)*-24;
hrsold=Math.floor(e_hrsold);
e_minsold=(hrsold-e_hrsold)*-60;
minsold=Math.floor((hrsold-e_hrsold)*-60);
seconds=Math.floor((minsold-e_minsold)*-60);
span_dt_dt.innerHTML=daysold+"天"+hrsold+"小时"+minsold+"分"+seconds+"秒 (勉强)" ;
}
show_date_time();
//-->
</SCRIPT>
</div>