Horse Profile: Differentiate between "Light" and "Dark" Grey in the Color Dropdown

I have entered multiple shows which, in their workmanship division, differentiate between "dark" and "light" grey. If we could select one of the other in the color dropdown on a horse's profile, rather than just "grey", it would be easier to enter and keep them properly sorted in classes. The simple "grey" would need to remain so horses who have this color currently don't have an error on their profile should their owners not update them.

Perhaps it could be a pattern option for horses with a grey coat if it isn't separated between light and dark