What is wrong with a blue light underneath?
Lights give important information. Wrong lights can confuse other drivers and maybe cause a crash. As a driver, if you see a white light you automatically expect it to represent a vehicle moving towards you. If you show a white light to the rear, a driver might think you are moving towards them and swerve. Similar confusion might be caused by a red light to the front. Blue is associated with the emergency services. Unless you are trying to impersonate a police vehicle, you should avoid using blue.
