lastOpened = document.getElementById("menu_avance-inicial");

function openMenu(pElement){
	
	if (lastOpened != null) lastOpened.style.display="none"; 
	
	document.getElementById('menu_avance-inicial').style.display="none"; 
	var id = pElement.attributes['href'].value;
	id = id.substr(id.indexOf("#")+1);
	var menu = document.getElementById(id);
	menu.style.display="block"; 
	lastOpened = menu;
	
	var position_top = "0px";
	
	var panel_derecha = document.getElementById('panel-derecho').clientHeight;
	var panel_izquierda = document.getElementById('panel-izquierdo').clientHeight;
	var panel_centro = document.getElementById(id).clientHeight;
	
	position_top = Math.max(Math.max(panel_derecha ,panel_izquierda), panel_centro);

	document.getElementById('pie').style.position = "relative";
	document.getElementById('pie').style.marginTop = "10px";
	document.getElementById('pie').style.height = "20px";
	document.getElementById('pie').style.top = (position_top - Math.max(panel_derecha ,panel_izquierda)) + "px";
	
	document.getElementById('principal').style.height = (position_top + 50) + "px";
	
	return false;
}

function closeMenu(pElement){
	pElement.parentNode.style.display="none"; 
	lastOpened = null;
	return false;
}