html倒计时代码

<SPAN id=span_dt_dt></SPAN>
<SCRIPT language=javascript>
<!--
//document.write("");
function show_date_time(){
window.setTimeout("show_date_time()", 1000);
BirthDay=new Date("6/07/2010 08:00:00");//这个日期是可以修改的
today=new Date();
timeold=(BirthDay.getTime()-today.getTime());
sectimeold=timeold/1000
secondsold=Math.floor(sectimeold);
msPerDay=24*60*60*1000
e_daysold=timeold/msPerDay
daysold=Math.floor(e_daysold);
e_hrsold=(e_daysold-daysold)*24;
hrsold=Math.floor(e_hrsold);
e_minsold=(e_hrsold-hrsold)*60;
minsold=Math.floor((e_hrsold-hrsold)*60);
seconds=Math.floor((e_minsold-minsold)*60);
span_dt_dt.innerHTML="据高考还有<align=center><p><font color=#A22900><p><font  size=4>"+daysold+"天"+hrsold+"小时"+minsold+"分"+seconds+"秒"+"<br></font><br></font>" ; // 这里你自己改。就是倒计时的样式，字体大小size=4 颜色是color
}
show_date_time();
//-->
</SCRIPT>