function openLayer() {
	NC = (document.layers);
	IE = (document.all);
	Opera = (document.getElementById);
	if(IE) document.all["layerAd"].style.display = "block";
	if(NC) document.layers["layerAd"].display = "block";
	if(Opera) document.getElementById("layerAd").style.display = "block";
}

function closeLayer() {
	NC = (document.layers);
	IE = (document.all);
	Opera = (document.getElementById);
	if(IE) document.all["layerAd"].style.display = "none";
	if(NC) document.layers["layerAd"].display = "none";
	if(Opera) document.getElementById("layerAd").style.display = "none";
}