// LAYERS //

// DETECTOR DE BROWSER //
	var dom = document.getElementById ? true:false;
	var nn4 = document.layers ? true:false;
	var ie4 = document.all ? true:false;

function prender(a,b){
	if(ie4){
		document.all[b].style.visibility="hidden";
		document.all[a].style.visibility="visible";
	}
	else if(nn4){
		document.layers[b].visibility="hidden";
		document.layers[a].visibility="visible";
	}
	else if(dom){
		document.getElementById(b).style.visibility = "hidden";
		document.getElementById(a).style.visibility = "visible";
	}
}

function prendernro(a,b){
	if(ie4){
		for ((i=1); i<(b+1); i++){
			document.all['contenido'+i].style.visibility="hidden";
		}
		document.all[a].style.visibility="visible";
	}
	else if(nn4){
		for ((i=1); i<(b+1); i++){
			document.layers.contenidoclip.document.layers['contenido'+i].visibility="hidden";
		}
		document.layers.contenidoclip.document.layers[a].visibility="visible";
	}
	else if(dom){
		for ((i=1); i<(b+1); i++){
			document.getElementById('contenido'+i).style.visibility = "hidden";
		}
		document.getElementById(a).style.visibility = "visible";
	}
}