.metal {
	background-image: url(images/metal.jpg);
	background-repeat: no-repeat;
}

.borde_alumnos {
	background-image: url(images/borde_alumnos.png);
	background-repeat: repeat-y;
}
.borde_noticias {
	background-image: url(images/borde_noticias.png);
	background-repeat: repeat-y;
}

.fondo_productos {
	background-image: url(../img_index/marco_productos.png);
	background-repeat: no-repeat;
}
.cuadrilatero {
	background-image: url(../index_ver3/cuadrilatero.jpg);
	background-repeat: no-repeat;
}