Complementary color poster color scheme

Quick answer：

A complementary color poster color scheme uses colors that are opposite each other on the color wheel, such as red and green, blue and orange, or yellow and purple. These colors are said to complement each other, which can create a striking and dynamic visual effect. In graphic design, complementary colors are often used to draw attention, convey a sense of balance, and evoke certain emotions. They are also used in color theory to create contrast and highlight key elements of a design.