Lightning is usually white, but it can be a variety of colors depending on what the light travels through to get to the viewer’s eyes. In snowstorms, lightning can appear pink or green. Particles in the atmosphere affect the color by absorbing or diffracting a portion of the white light.
According to Encyclopedia Britannica, lightning is the visible discharge of electricity that happens when a region of a cloud acquires a positive or negative electrical charge that is sufficient enough to break down the resistance of air. Usually there is a large volume of positive charge in the upper regions of the cloud, a large negative charge in the center or a small positive charge in the lower regions.