onload = function() {
	if (screen.width > 1024) {
		images = new Array("/fotos/1440/agb01.jpg");
	}	else {
		images = new Array("/fotos/1024/agb01.jpg");
	}
	rand = Math.floor(Math.random()*images.length);
	img = images[rand];
	document.body.style.background = "url("+img+") no-repeat fixed";
}