I love the head cannon but this got me thinking just a little.
I went into a deep dive about negative colors but every place that I read, the answer was the same negative colors basically equals inverted colors (screen shots attached for proof/research purposes. Images taken from google)
Okay and so that got me thinking, ok so the colors weren't adding up so i plugged them into procreate. And here is my results.
(I am so sorry i screen shotted your art) Normal image:
But as you can see the colors don't line up very well, especially the blue to red or the yellow turning purple.
So I looked into color blindness and i believe ghost (or at least Danny) have Tritanopia. (One of the main spectrums of colors people may see, a form of color blindness)
If we look back to the sky in the series screen shot we can see blue goes to like a green color (which you also did), and what do you know Tritanopia is the only one that has blue to green. We also see yellow to purple which isn't on here but yellow to pink is close.
I couldn't find anything on the gray to blue Sam's hair highlight changes into. It could be just like how a crow reflects blue to us her hair also does that.
This was also a 2000's cartoon where they were on a budget and might not have put too much thought into it.
Anyway- again so sorry for the screen shots on your art pieces, and again how much I actually love this head cannon. What are your thoughts @starlightbreathh ??
Ether way Danny still won't be able to tell his colors apart.