function showLayer(layerName, shadowLayerName){
	if (document.getElementById){ // Netscape 6 and IE 5+
		var targetElement = document.getElementById(layerName);
		var shadowElement = document.getElementById(shadowLayerName);
		targetElement.style.top = shadowElement.style.top;
	targetElement.style.visibility = 'visible';
	}
}


function hideLayer(layerName){
	if (document.getElementById) {
		var targetElement = document.getElementById(layerName);
		targetElement.style.visibility = 'hidden';
	}
}