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color

The punctuation can influence the meaning:
            red, white, and blue flags (solid-colored flags), red-white-and-blue flags (tricolors).

Do not hyphenate compound color modifiers unless in Webster's or unless both elements are colors of equal value:
            blue-black sky, gray-green eyes
but     bluish black sky, lemon yellow dress
            jade green lake, cobalt blue dish, dark blue suit

To avoid ambiguity, note:
            deep-green water
            light-blue suit (color)
            light blue suit (weight)

See also ADJECTIVES AND ADVERBS, PUNCTUATION OF, HYPHEN.