What color and what color

Quick answer：

This question is asking about the combination of two colors. In design, color theory discusses how colors interact with each other. The relationship between colors can be described by color wheels, which categorize colors into primary, secondary, and tertiary colors. Complementary colors are opposite each other on the color wheel and create a strong contrast when combined. Analogous colors are next to each other on the color wheel and provide a harmonious blend. Monochromatic colors are different shades of the same color, while analogous colors are those that are adjacent on the color wheel.