Colors make up nine shades of light and shade.

If black and white are mixed in arithmetic proportion, a 9-level lightness color scale is established. According to the lightness color scale, it can be divided into three lightness tones, 1 is the deepest and 9 is the brightest. The third level close to black (1, 2,3) is composed of dark color, which is called low lightness tone. The middle three levels (4, 5, 6) are composed of colors with medium brightness, which is called medium brightness tone. The third level (7, 8, 9) close to white is composed of bright colors, which are called high-definition tones.

Low lightness tone (dark tone) has the characteristics of calmness, massiness, tenacity and depression;

The tone in the middle of Ming Dynasty is soft, implicit, clear and solemn.

High-definition colors are bright, exciting, elegant and soft.