网站运行时间统计代码：快速展示网站运行天数

<div id='span_dt_dt'></div>
<script language='javascript'>
function show_date_time() {
window.setTimeout('show_date_time()', 1000);
BirthDay = new Date('8/21/2017 23:32:13');
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 = (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 = '<font style=color:#ffffff>' + daysold + '</font> 天 <font style=color:#ffffff>' + hrsold + '</font> 时 <font style=color:#ffffff>' + minsold + '</font> 分 <font style=color:#ffffff>' + seconds + '</font> 秒';
}
show_date_time();
</script>
<style>
#span_dt_dt {
   display: block;
   margin: 0 auto;
   text-align: center;
}
</style>
<p>将上述CSS代码添加到页面的<head>标签内即可。</p>