You can make the Inverted Light Mode Color Scheme, usable if you replace the dark colors with the inverted version of light colors and if you replace the light colors with the inverted version of the dark colors.
Anyway the original DF pallete is made of colors that have the value 0 and/or 128 and 0 and/or 255 and one exception (light gray) that has the average of the value that arent present at both rules (128 and 255, (128+255)/2=192).
You can change the rule to allow the color to be made of 128 and/or 0 and 128 and/or 256 and the result will be similar to what I described at the first line of this comment. (0+256)/2 = 128, so you will need to pick an value to the second gray, I decided to leave dark gray as 128 and light gray as 192.
[BLACK_R:0]
[BLACK_G:0]
[BLACK_B:0]
[BLUE_R:0]
[BLUE_G:0]
[BLUE_B:128]
[GREEN_R:0]
[GREEN_G:128]
[GREEN_B:0]
[CYAN_R:0]
[CYAN_G:128]
[CYAN_B:128]
[RED_R:128]
[RED_G:0]
[RED_B:0]
[MAGENTA_R:128]
[MAGENTA_G:0]
[MAGENTA_B:128]
[BROWN_R:128]
[BROWN_G:128]
[BROWN_B:0]
[LGRAY_R:192]
[LGRAY_G:192]
[LGRAY_B:192]
[DGRAY_R:128]
[DGRAY_G:128]
[DGRAY_B:128]
[LBLUE_R:128]
[LBLUE_G:128]
[LBLUE_B:255]
[LGREEN_R:128]
[LGREEN_G:255]
[LGREEN_B:128]
[LCYAN_R:128]
[LCYAN_G:255]
[LCYAN_B:255]
[LRED_R:255]
[LRED_G:128]
[LRED_B:128]
[LMAGENTA_R:255]
[LMAGENTA_G:128]
[LMAGENTA_B:255]
[YELLOW_R:255]
[YELLOW_G:255]
[YELLOW_B:128]
[WHITE_R:255]
[WHITE_G:255]
[WHITE_B:255]
