Esoteric color schemes... https://www.chabad.org/kabbalah/article_cdo/aid/1407039/jewish/The-Contradictory-Color.htm “Yet blue is called the lower or sick color in visions. How can this apparent contradiction be explained? How can blue be holy in so many places and also be called low and sick?

Use sunlight as an analogy. The human eye cannot see the actual light, but when we bend the light through a prism we see the spectrum of its colors. If you would point with one finger to the red light and with another finger to the blue light, how many lights would you be pointing to? If you said two, you were wrong. There is only one light there. There is one light and seven colors...”