不随页面滚动的元素(<回到顶部>或者是页面顶部信息之类的)

.ToTop{
    position: fixed;//类似于absolute,不过其包含块是视窗本身
    bottom: 0;
    background: black;
     90px;
    height: 90px;
    line-height: 23px;
    z-index: 9999;
    opacity: 0.6;//Chrome
/*以下针对IE*/ filter: alpha(opacity
=60); _bottom: auto; _ 100%; _position: absolute; _top: expression(eval(document.documentElement.scrollTop+document.documentElement.clientHeight-this.offsetHeight-(parseInt(this.currentStyle.marginTop,10)||0)-(parseInt(this.currentStyle.marginBottom,10)||0))); }
原文地址:https://www.cnblogs.com/TiestoRay/p/2650601.html