Complementary colors
These are the color pairings that create the greatest eye-catching contrast; another name for them is "opposite colors," because the colors in each pair are diametrically opposed to one another. On the traditional color wheel, they are red and green, yellow and violet, and blue and orange; however, the CMYK and RGB color models use red and cyan, green and magenta, and blue and yellow respectively. The classic color wheel shows red and green, yellow and violet, and blue and orange.
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