function OpenLayer(l,t){
	if(l != ''){
		divWidth = document.getElementById(l).style.width;
		divWidth = divWidth.replace("px","")
		screenwidth = (screen.width-divWidth)/2+"px";
		if(t != ''){
			document.getElementById(l).style.top = t+"px";
		}
		document.getElementById(l).style.left = screenwidth;
		document.getElementById(l).style.visibility='visible';
	}
}
function CloseLayer(m){
	if(m != ''){
		document.getElementById(m).style.visibility='hidden';
	}
}