Hey!
I quite liked your game, I find the concept to be very creative; it's unlike anything I've played before! The fact that some colours heal while others hurt the player is a nice touch.
However, I found that, when in shaded grounds, the player can still receive damage from the underlying original colour. I don't know if this is intended, but creating a "safe zone" in shadows could create interesting puzzles!
Anyhoo,
Cheers!