I've always said lime and cyan, but i know others don't know it like that so maybe you could let it accept light green, dark green, light blue, dark blue. Keep the names the same, but adjust the regex.
In the 15 player lobby update, new colors were added (rose, maroon ,grey, banana, coral) and tan was readded. And if you do update this quiz, accept peach for coral, light pink for rose and light yellow for banana. If you don't believe me, check, and if it doesn't work you're on an older version and have to update.