Yin and Yang are two opposing forces active in the Universe. Yin exists in yang and yang exists in yin. This perpetually changing combination creates Qi. The transitional periods between seasons are dominated by Earth. Here are some of the properties, shapes and colors of the five types of active Qi as their names imply.
Water runs downwards, liberal.
Wavy, black and dark blue. Wood grows upwards, enduring. Fire spreads in all directions, radiant and hot. Triangular, red, orange, purple and pink. Metal pierces inwards, sharp and pointing.