Yes. What I do is use Coolors first to pick the actual palette:
https://coolors.co/
Then I put the exact HEX color codes into my Gamma prompt.
For example:
“Use this color palette throughout the presentation:
- Navy: #0b1f33
- Blue: #1d4ed8
- Light gray: #f3f4f6
- White: #ffffff
- Near black: #111827
Whenever Navy or Blue is used as a background, text must be White. Whenever White or Light Gray is used as a background, text must be Near Black.”
That way Gamma is not deciding what “contrasting colors” means — I have already given it the actual colors and the rules for using them.
I do this because art class was my weakest subject in school. And when I was getting married I discovered that “white” apparently meant ivory, cream, eggshell, pearl, champagne, and about 47 other colors, my mind was blown. So now I let Coolors do the artistic thinking and just give Gamma the numbers.