Classic red and blue color blocking

Quick answer：

Classic red and blue color blocking refers to a design technique that involves using the colors red and blue in contrasting or complementary ways. This style is often found in fashion, interior design, and graphic design. The technique creates a striking visual effect by juxtaposing these high-contrast colors, which can evoke a sense of energy and boldness. In fashion, for example, it is commonly seen in bold color combinations like red blazers with blue jeans.