.linea-azul {
	background-image: url(imagenes_ficheros/linea-azul.gif);
	background-repeat: repeat-y;
	background-position: right top;
}
.linea-azul-izquierda {
	background-image: url(imagenes_ficheros/linea-azul.gif);
	background-repeat: repeat-y;
	background-position: left top;
}