//-----------------------------------------------------
	//------  LAYER MANAGEMENT --------------------------
	//-----------------------------------------------------
	var layeron = '';
	var detect = navigator.userAgent.toLowerCase();
	
	function initlay() {
		// Layers: there would be one for each layer present into the page  
		if ((detect.search('mozilla') != -1) || (detect.search('firefox') != -1)){
			obj_1 = eval('div_1.style');
			obj_1.visibility = 'hidden';
			obj_2 = eval('div_2.style');
			obj_2.visibility = 'hidden';
		}
		if (document.layers) {	
			obj_1 = eval(document.div_1);
			obj_1.visibility = 'hide';
			obj_2 = eval(document.div_2);
			obj_2.visibility = 'hide';
		}
		var layeron = '';
		return;
	}
	
	function switchlay(layin) {
		// Azzeramento dei vari layers 
		initlay();
		// Accensione del layer richiesto 
		if ((detect.search('mozilla') != -1) || (detect.search('firefox') != -1)){
			objnew=eval(layin+'.style');
			objnew.visibility='visible';
		}
		if (document.layers) {
			objnew=eval('document.'+layin);
			objnew.visibility='show';
		}
		layeron = layin;
		return;
	}
	//-----------------------------------------------------