html 遮罩

<div class="overlay"></div>

.overlay{

position: fixed;
z-index: 100;
width: 100%;height: 100%;
top: 0;left: 0;
filter: alpha(opacity=50);opacity: 0.3;
overflow: hidden;
background-color: #000;
}

转载于:https://www.cnblogs.com/fll369/archive/2012/10/12/2720913.html