function div_switch (div,divvar)   {
	var alto=$(div).getStyle('height').toInt();
	var ancho=$(div).getStyle('width').toInt();
	$(div).getStyle('visibility')=='visible'?($(div).setStyle('visibility','hidden')):(
	divvar.write(div),
	$(div).setStyle('top',(window.getHeight()-alto)/2+"px"),
	$(div).setStyle('left',(window.getWidth()-ancho)/2+"px"),
	$(div).setStyle('visibility','visible')); 
}

sfHover = function() {
	var sfEls = document.getElementById("menu").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
		}
	}
}
function bio_switch ()   {
	$('bio').getStyle('visibility')=='visible'?($('bio').setStyle('visibility','hidden'),$('este').setStyle('height','450px')):(
	$('bio').setStyle('visibility','visible')); 
	alargaizq();
}
function alargaizq(){
	var altura=$('este').getStyle('height');
	$('izquierda2').setStyle('height',altura);
}
function alargader(){
	var altura=$('izquierdaportada').getStyle('height');
	$('derecha').setStyle('height',altura);
}
if (window.attachEvent) window.addEvent("load", sfHover);