function derecha(capa){
	ancho = (document.all) ? document.body.offsetWidth : window.innerWidth
	anchocapa = capa.width
	capa.xpos = ancho-parseInt(anchocapa)
	capa.left = capa.xpos
}

function centro_v(capa, margen){
	alto = (document.all) ? document.body.offsetHeight : window.innerHeight
	altocapa = capa.height
	capa.ypos = margen+(alto-parseInt(altocapa))/2
	capa.top = capa.ypos
}


function mostrarObjeto(obj) {
 obj.visibility = "visible"
}


function ocultarObjeto(obj) {
 obj.visibility = "hidden"
}