急...js弹层，在火狐浏览器上面弹，关闭层以后，页面的滚动条就不会见，在google浏览器也一样。

[陌城灬流年閣]

var mybg = document.createElement("div");
    //弹出层
    function d_x(){  
         
    var h = document.body.clientHeight; 
    var w = document.body.clientWidth;
       
    myAlert = document.getElementById("alert"); 
    myAlert.style.display = "block";  
    myAlert.style.position = "absolute";
     
    
    myAlert.style.top = (h/2)+"px";  
    myAlert.style.left = (w/2)+"px";  
    //myAlert.style.marginTop = "-200px";  
    //myAlert.style.marginLeft = "-250px";  
    
    mybg.setAttribute("id","mybg");  
    mybg.style.background = "#000";
    mybg.style.display = "block"; 

    mybg.style.width = "100%"; 
    mybg.style.height = h+"px";  
    mybg.style.position = "absolute";  
    mybg.style.top = "0";  
    mybg.style.left = "0";  
    mybg.style.zIndex = "500";  
    mybg.style.opacity = "0.5";  
    mybg.style.filter = "Alpha(opacity=40)";  
    document.body.appendChild(mybg);  


//取消层
myAlert.style.display = "none";  
mybg.style.display = "none"; 

[陌城灬流年閣]

在线。自己顶下

[陌城灬流年閣]

大神们。出来冒个泡吧

[泡泡鱼_]

不知道你问的什么。如果描述不清楚，就贴代码，上效果图。比你这样问问题好得多得多