.sub{
background-image: url(../imagenes/click.jpg);
background-repeat:no-repeat;
}
.sub:hover {
background-image: url(../imagenes/click2.jpg);
background-repeat:no-repeat;
}
.fondito{
background-image: url(../imagenes/fdto1.gif);
background-repeat:repeat;
}
.fondito:hover {
background-image: url(../imagenes/fdto2.gif);
background-repeat:repeat;
}
.er{
background-image: url(../imagenes/er1.jpg);
background-repeat:repeat;
}
.er:hover {
background-image: url(../imagenes/er2.jpg);
background-repeat:repeat;
}