Can you get comparative and superlative form of the colors?

Like other adjectives, colors become comparative and superlative with the suffixes -er and -est.

This could apply to literal colors, as pure red is redder than an almost-red shade of brown. It is probably more common to hear these in a figurative context. For example, in the U. S. a "red" State is politically Republican while a "blue" State is Democrat. The state with the highest percent of Republicans would be the reddest. The most environmentally friendly of some companies or technologies wold be the greenest. Since "blue" also means "sad," I could say I was blue when I lost yesterday's newspaper on the bus but I was bluer when I lost my girlfriend.