样式一：

1. 将代码放入 functions.php

一般在主题根目录：网站 /usr/themes/ 主题

修改一下你自己的网站时间

    // 设置时区
    date_default_timezone_set('Asia/Shanghai');
    /**
     * 秒转时间，格式 年 月 日 时 分 秒
     *
     */
    function getBuildTime() {
        // 在下面按格式输入本站创建的时间
        $site_create_time = strtotime('2019-06-23 00:00:00');
        $time = time() - $site_create_time;
        if (is_numeric($time)) {
            $value = array(
                "years" => 0, "days" => 0, "hours" => 0,
                "minutes" => 0, "seconds" => 0,
            );
            if ($time >= 31556926) {
                $value["years"] = floor($time / 31556926);
                $time = ($time % 31556926);
            }
            if ($time >= 86400) {
                $value["days"] = floor($time / 86400);
                $time = ($time % 86400);
            }
            if ($time >= 3600) {
                $value["hours"] = floor($time / 3600);
                $time = ($time % 3600);
            }
            if ($time >= 60) {
                $value["minutes"] = floor($time / 60);
                $time = ($time % 60);
            }
            $value["seconds"] = floor($time);
    
            echo '<span class="btime">'.$value['years'].
            '年'.$value['days'].
            '天'.$value['hours'].
            '小时'.$value['minutes'].
            '分</span>';
        } else {
            echo '';
        }
    }

2. 修改 footer.php
在页脚选择合适的位置加入:

<?php getBuildTime(); ?>

样式二：

修改 footer.php 在页脚选择合适的位置加入:

    本站已安全运行:
<span id="momk"></span>
<script language=javascript>
function show_date_time(){
window.setTimeout("show_date_time()", 1000);
BirthDay=new Date("05-06-2016 12:12:24");//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);
momk.innerHTML=daysold+"天"+hrsold+"小时"+minsold+"分"+seconds+"秒" ;
}
show_date_time();
</script>
<style>
#momk{animation:change 10s infinite;font-weight:800; }
@keyframes change{0%{color:#5cb85c;}25%{color:#556bd8;}50%{color:#e40707;}75%{color:#66e616;}100% {color:#67bd31;}}
&lt;/style&gt;</code></pre><h2>样式三：</h2><p><strong>修改 footer.php 在页脚选择合适的位置加入:</strong></p><pre><code class="lang-php">    &lt;span id=&quot;momk&quot;&gt;&lt;/span&gt;&lt;span id=&quot;momk&quot; style=&quot;color: #ff0000;&quot;&gt;&lt;/span&gt;
&lt;script type=&quot;text/javascript&quot;&gt;
function NewDate(str) {
str = str.split('-');
var date = new Date();
date.setUTCFullYear(str[0], str[1] - 1, str[2]);
date.setUTCHours(0, 0, 0, 0);
return date;
}
function momxc() {
var birthDay =NewDate(&quot;2016-5-6&quot;);
var today=new Date();
var timeold=today.getTime()-birthDay.getTime();
var sectimeold=timeold/1000
var secondsold=Math.floor(sectimeold);
var msPerDay=24*60*60*1000; var e_daysold=timeold/msPerDay;
var daysold=Math.floor(e_daysold);
var e_hrsold=(daysold-e_daysold)*-24;
var hrsold=Math.floor(e_hrsold);
var e_minsold=(hrsold-e_hrsold)*-60;
var minsold=Math.floor((hrsold-e_hrsold)*-60); var seconds=Math.floor((minsold-e_minsold)*-60).toString();
document.getElementById(&quot;momk&quot;).innerHTML = &quot;本站已安全运行&quot;+daysold+&quot;天&quot;+hrsold+&quot;小时&quot;+minsold+&quot;分&quot;+seconds+&quot;秒&quot;;
setTimeout(momxc, 1000);
}momxc();
&lt;/script&gt;  &lt;style&gt;
#momk{animation:change 10s infinite;font-weight:800; }
@keyframes change{0%{color:#5cb85c;}25%{color:#556bd8;}50%{color:#e40707;}75%{color:#66e616;}100% {color:#67bd31;}}
&lt;/style&gt;</code></pre>