function mostrar(capa){for (i=1;i<=8;i++){if (i==capa){document.getElementById(i).style.visibility="visible";}else{document.getElementById(i).style.visibility="hidden";}}}
function ocultar(capa){document.getElementById(capa).style.visibility="hidden";} 
function color(boton){document.getElementById(boton).style.background="url(imagenes/fon_menu3.gif)";}
function restaurar(boton){document.getElementById(boton).style.background="url(imagenes/fon_menu.gif)";}