stuHover = function() {
	var cssRule;
	var newSelector;
	for (var i = 0; i < document.styleSheets.length; i++)
		for (var x = 0; x < document.styleSheets[i].rules.length ; x++)
			{
			cssRule = document.styleSheets[i].rules[x];
			if (cssRule.selectorText.indexOf("LI:hover") != -1)
			{
				 newSelector = cssRule.selectorText.replace(/LI:hover/gi, "LI.iehover");
				document.styleSheets[i].addRule(newSelector , cssRule.style.cssText);
			}
		}
	var getElm = document.getElementById("nav").getElementsByTagName("LI");
	for (var i=0; i<getElm.length; i++) {
		getElm[i].onmouseover=function() {
			this.className+=" iehover";
		}
		getElm[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" iehover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", stuHover);



		function mostrarCapa1(mostrar){
				capa= document.getElementById("capa1");
				if (mostrar)
				  capa.style.visibility="visible";
				else
				  capa.style.visibility="hidden";
			}
			
		function mostrarCapa2(mostrar){
				capa= document.getElementById("capa2");
				if (mostrar)
				  capa.style.visibility="visible";
				else
				  capa.style.visibility="hidden";
			}
		
		function mostrarCapa3(mostrar){
				capa= document.getElementById("capa3");
				if (mostrar)
				  capa.style.visibility="visible";
				else
				  capa.style.visibility="hidden";
			}
	      
		  var ventana;
          function abrirVentana(url){
              ventana=window.open(url,'ventana','status=no, locationbar=no, toolbar=no, titlebar=no, scrollbars=yes, resizeable=yes, alwaysRaised=no, directories=no, menubar=no, location=no, width=500, height=500, left = 50, top = 50')
          }