A question often asked is about how to change the link colors for moderator and administrator user listed in the Who’s Online box and on the Who’s Online page. It’s relatively easy, you will need to edit the colors for “font color 2” and “font color 3” in Administration Panel -> Styles Admin -> Management.
Like I mentioned previously in the guide while on the topic of styles, phpBB uses field values stored in the database for colors, background images and fonts. The colors used for moderator and administrator user links cannot be defined in the external stylesheet (CSS file) so they need defined in the style (stored in the database). In the default subSilver template, “font color 3” is also used for table headers.