Oddly enough, there are forbidden colors that are invisible to the eye.
"Forbidden colors" are those colors that are beyond the control of the human eye, that is, a person is not able to see them due to the fact that they consist of several shades that compensate for each other in human eyes. A person cannot even imagine them, and not just see them. Yellow-blue is a color with shades of blue and yellow, while red-green is a color that is both red and green at the same time.
The human eye is designed in such a way that the retina has special neurons, which are also called "neuronal opponents".
They light up when a person sees red and this burst of activity tells the brain exactly what a person sees red in front of him. The same opponents of neurons are suppressed in green. The same thing happens with yellow-blue, yellow activates, and blue suppresses their activity. As a result of our brains being able to decode colors, we will never be able to see these colors coming from one source.