body {
	margin: 0px;
	background: url(tile5.gif);
}
#horizonte {
	overflow: visible;
	position: absolute;
	visibility: visible;
	height: 0;
	width: 100%;
	top: 50%;
	background-repeat: repeat-x;
}
#contenedor {
	overflow: visible;
	position: relative;
	visibility: visible;
	left: 50%;
	height: 600px;
	width: 900px;
	margin-top: -300px;
	margin-left: -450px;
}