.st3 {  background-attachment: fixed; background-color: #FFFFFF; background-image: none; background-repeat: no-repeat}
.bg2 {  background-attachment: fixed; background-color: #FFFFFF; background-image:  url(img/fondon.gif); background-repeat: no-repeat}
.mf { background-attachment: fixed; background-color: #990000; background-image: url(web/mf/fondo.gif); background-repeat: no-repeat }