I have this in my userContent.css file, same folder. I think the last lines are to make the /*text*/ work properly
/* Quote Levels Colors */
blockquote[type=cite] {
color: navy !important; background-color: RGB(245,245,245) !important;
}
blockquote[type=cite] blockquote {
color: maroon !important; background-color: RGB(235,235,235) !important;
}
blockquote[type=cite] blockquote blockquote {
color: green !important; background-color: RGB(225,225,225) !important;
}
blockquote[type=cite] blockquote blockquote blockquote {
color: purple !important; background-color: RGB(215,215,215) !important;
}
blockquote[type=cite] blockquote blockquote blockquote blockquote {
color: teal !important; background-color: RGB(205,205,205) !important;
}
/* remove the / * or _ tags from news text messages */
..moz-txt-tag { display: none; }