On a hot summer day, white clothing feels cooler than other colors due to reflecting—not absorbing—sunlight. Other colors like blue or black, will undergo a heating effect as they absorb light. To circumvent this heating effect in colored cooling films, researchers drew inspiration from nanostructures in butterfly wings.

On a hot summer day, white clothing feels cooler than other colors due to reflecting—not absorbing—sunlight. Other colors like blue or black, will undergo a heating effect as they absorb light. To circumvent this heating effect in colored cooling films, researchers drew inspiration from nanostructures in butterfly wings.