There is no "series". These are all the same "style". You can specify any "background-color" you like. Try using hex codes and you'll see there are millions of 'em. I don't think anyone wants each posted as a new "style" and it makes the person posting it appear to be a dolt.
Lanik said about Firefox: Mod - Turn Progress Bar DarkBlue on Mar 19 2008
PeCet said about Firefox: Mod - Turn Progress Bar DarkBlue on Feb 28 2007
Weishun said about Firefox: Mod - Turn Progress Bar DarkBlue on Oct 28 2006