复制代码 代码如下:
function show(){ var cover = document.getelementbyid(cover);
cover.style.width = document.documentelement.scrollwidth+px;
cover.style.height = document.documentelement.scrollheight+px;
cover.style.display = block;
}
#cover{
background:gray;
position:absolute;
left:0px;
top:0px;
display:none;
z-index:20;
filter:alpha(opacity=60);
opacity:0.6 !important;
}