The “Shimmer” effect in Keynote uses white sparkles. How can I change them to red sparkles?

I would like to modify one of the keynote standard animations to have the white sparkles be red. I'd like to have the white animation below to be red in color. My setup is currently Keynote 13.1 (7037.0.101) on macOS Venture 13.4.1 (c) **Is there a color palette I can modify to achieve this?**