//*** Efecto de transicion alpha
var efecto_guay = new viewer($('si_contendor').getChildren(),{
	mode: 'alpha',
	fxOptions: {duration:750},
	onWalk: function(current_index){
		handles.removeClass('active');
		handles[current_index].addClass('active');
	}				
});			

var handles = $$('#si_menu div');
handles.each(function(el,i){el.addEvent('click',efecto_guay.walk.bind(efecto_guay,i));});

function sobre_img(id){
	var nombre="img_bot_"+id;
		document.getElementById(nombre).className="img_on";
}
function fuera_img(id){
	var nombre="img_bot_"+id;
	var menu="menu_"+id;
	if(document.getElementById(menu).className != "si_boton_menu activate"){
		document.getElementById(nombre).className="img_off";
	}
}