Related Clues:

• Secret Service agent's wear
• Subtleties, as of meaning
• Cool cats may wear them
• Color tones
• Tones
• Rainbow features
• Turns blue, perhaps
• Applications for windows
• Rainbow sights
• Shadings
• Array on a wheel, maybe
• Delicate colors
• Emerald and ruby, e.g.
• Colorist's choices
• Slight shadings