在网站页面右下角添加一个“回到顶部”的按钮，手机和电脑通用，通过CSS加JavaScript即可实现，代码如下：
css/js
/* 回到顶部 手机电脑都显示 */
#backToTop {
position: fixed !important;
right: 20px !important;
bottom: 25px !important;
width: 42px !important;
height: 42px !important;
line-height: 42px !important;
font-size: 18px !important;
background: #222 !important;
color: #fff !important;
border-radius: 50% !important;
text-align: center !important;
cursor: pointer !important;
z-index: 99999 !important;
opacity: 0 !important;
visibility: hidden !important;
transition: all 0.3s ease !important;
}
#backToTop.show {
opacity: 1 !important;
visibility: visible !important;
}
#backToTop:hover {
background: #007cba !important;
}
<div id="backToTop">↑</div>
<script>
const backToTopBtn = document.getElementById('backToTop');
window.addEventListener('scroll', function(){
if (window.scrollY > 150) {
backToTopBtn.classList.add('show');
} else {
backToTopBtn.classList.remove('show');
}
});
backToTopBtn.addEventListener('click', function(){
window.scrollTo({top:0,behavior:'smooth'});
});
</script>
