Why do darker colors absorb more heat than lighter colors? This is because of the visible light spectrum. Regular white light is made of different wavelengths: red, orange, green, yellow, indigo, and violet.
A darker colored object absorbs a lot wavelengths of light and converts them into heat, so the object gets warm. An example is black, which absorbs all of the wavelengths. White or lighter colors stay cooler because they reflect the wavelengths, keeping them cool.