function showLayer(layerid) {
    lay_a = document.getElementById(layerid+"_a"); 
	lay_a.style.position = "relative";
    lay_a.style.visibility = "visible"; 
	  
	img = document.getElementById(layerid+"_i");
	img.src = "image/dot.gif";
	img.alt = "-";
	
	lay = document.getElementById(layerid);
	lay.style.background = "#f0f0f0";
}

function hideLayer(layerid) {  
    lay_a = document.getElementById(layerid+"_a");
	lay_a.style.position = "absolute";
    lay_a.style.visibility = "hidden";

	img = document.getElementById(layerid+"_i");
	img.src = "image/plus.gif";
	img.alt = "+";

	lay = document.getElementById(layerid);
	lay.style.background = "white";
}

function toggleLayer(layerid) {  
    layer = document.getElementById(layerid+"_a");
	if (layer.style.visibility == "visible")
		hideLayer(layerid);
	else
		showLayer(layerid);
}


function showscreen(name,url,width,height) { 
	window.open(url,name,'align=center,toolbar=no,status=no,location=no,directories=no,resizable=yes,scrollbars=yes,width='+width+',height='+height+',menubar=no')
}

function showhand() {
	window.cursor = hand;
}