Improve color logic

[Wolfr]

Colors needs better logic;

• color-blue-400 refers to a blue with about 40% lightness
• we should check this logic for all colors; but perceived lightness is different for every color, so we need to come up with an overall color scheme

Figma file: https://www.figma.com/file/RHCjIYPkQGOj8CPQ7WNtY5/Jungle-colors?node-id=0%3A44