Code:
gui_text_color = [black], white, RRGGBBAA
gui_text_outline = [00], RRGGBBAA, AA
gui_text_shadow = [00], RRGGBBAA, AA
gui_text2_color = black, [white], RRGGBBAA
gui_text2_outline = [FF], RRGGBBAA, AA
gui_text2_shadow = [00], RRGGBBAA, AA
The gui_text_* options affect gridflow GUI modes (grid, flow, flow-z). The gui_text2_* options affect the coverflow modes (coverflow3d, coverflow2d, frontrow, vertical, carousel).
Set the gui_text_color to black, white, or an 8 character hexadecimal representation of the colour where RR = red, GG = green, BB = blue and AA = alpha (transparency). The outline and shadow of the text can be set to be a fully selectable hex colour, like the main one. If only a 2 character code is given (AA) then the colour of the shadow and outline will be white if the main colour is dark and black if the main colour is bright.