Answer:
the change in day light is affected by the Earth's orbit around the Sun and the Earth's rotation. The tilt of the Earth is 23 degrees so as it spins the day goes on and gets darker when your area is farthest away from the Sun. The orbit around the Sun, isn't a circle, it is in fact a oblonge (oval) shape. So when the Earth is farthest away from the Sun the Earth isn't getting as much Sun as when it is closer in the Summer. That is why it is darker in the Winter.