<div class="header-clock-wrapper">
<span id="beijing-time">00:00:00</span>
</div>

<style>
/* 强制水平排列，防止竖着掉下来 */
.header-clock-wrapper {
display: block !important;
white-space: nowrap !important; /* 禁止换行 */
min-width: 100px !important;
text-align: center;
}

#beijing-time {
color: #333; /* 如果背景是深色请改为 #ffffff */
font-family: monospace;
font-size: 16px;
font-weight: bold;
}
</style>

<script>
function updateClock() {
const options = {
timeZone: 'Asia/Shanghai',
hour: '2-digit',
minute: '2-digit',
second: '2-digit',
hour12: false
};
const formatter = new Intl.DateTimeFormat('en-GB', options);
document.getElementById('beijing-time').textContent = formatter.format(new Date());
}
setInterval(updateClock, 1000);
updateClock();
</script>