JavaScript popup layer effect

Author：Eve Cole Update Time：2009-06-11 16:22:38

function sAlert(str){
var msgw,msgh,bordercolor;
msgw=400; //Width of prompt window
msgh=100;//The height of the prompt window
titleheight=25 //Prompt window title height
bordercolor="#336699";//Border color of the prompt window
titlecolor="#99CCFF";//Title color of the prompt window

var sWidth,sHeight;
sWidth=document.body.offsetWidth;
sHeight=screen.height;
var bgObj=document.createElement("div");
bgObj.setAttribute('id','bgDiv');
bgObj.style.position="absolute";
bgObj.style.top="0";
bgObj.style.background="#777";
bgObj.style.filter="progid:DXImageTransform.Microsoft.Alpha(style=3,opacity=25,finishOpacity=75";
bgObj.style.opacity="0.6";
bgObj.style.left="0";
bgObj.style.width=sWidth + "px";
bgObj.style.height=sHeight + "px";
bgObj.style.zIndex = "10000";
document.body.appendChild(bgObj);

var msgObj=document.createElement("div")
msgObj.setAttribute("id","msgDiv");
msgObj.setAttribute("align","center");
msgObj.style.background="white";
msgObj.style.border="1px solid " + bordercolor;
msgObj.style.position = "absolute";
msgObj.style.left = "50%";
msgObj.style.top = "50%";
msgObj.style.font="12px/1.6em Verdana, Geneva, Arial, Helvetica, sans-serif";
msgObj.style.marginLeft = "-225px" ;
msgObj.style.marginTop = -75+document.documentElement.scrollTop+"px";
msgObj.style.width = msgw + "px";
msgObj.style.height =msgh + "px";
msgObj.style.textAlign = "center";
msgObj.style.lineHeight="25px";
msgObj.style.zIndex = "10001";

var title=document.createElement("h4");
title.setAttribute("id","msgTitle");
title.setAttribute("align","right");
title.style.margin="0";
title.style.padding="3px";
title.style.background=bordercolor;
title.style.filter="progid:DXImageTransform.Microsoft.Alpha(startX=20, startY=20, finishX=100, finishY=100,style=1,opacity=75,finishOpacity=100);";
title.style.opacity="0.75";
title.style.border="1px solid " + bordercolor;
title.style.height="18px";
title.style.font="12px Verdana, Geneva, Arial, Helvetica, sans-serif";
title.style.color="white";
title.style.cursor="pointer";
title.innerHTML="Close";
title.onclick=function(){
document.body.removeChild(bgObj);
document.getElementById("msgDiv").removeChild(title);
document.body.removeChild(msgObj);
}
document.body.appendChild(msgObj);
document.getElementById("msgDiv").appendChild(title);
var txt=document.createElement("p");
txt.style.margin="1em 0"
txt.setAttribute("id","msgTxt");
txt.innerHTML=str;
document.getElementById("msgDiv").appendChild(txt);
}