They mean the same thing. The way the word "reflection" is used is odd. I'll explain that later. First, I'll explain the grammar. The first sentence is in the active voice. It tells us directly who or what is doing something. It tells us who or what is acting. The subject of the sentence is "bright lights." What "reflected different colors?' The bright lights "reflected different colors." The second is in the passive voice. If we just said "Different colors were reflected on the snow," that would be a correct sentence, but it has no subject. In the passive voice, something is happening but we don't know who or what is making it happen. However, by adding the phrase "by bright lights," the sentence still tells us who acted. The passive voice is a favorite of administrators. They can say "Mistakes were made" without having to say who made the mistakes. As a matter of writing style, the active voice is strong and direct. The passive voice is soft and vague. Both sentences use "to reflect" in an odd way. The first sentence is from a published book. I don't want to say the author is wrong. But usually we think of "reflection" as something that the surface does. A mirror reflects your face. A still lake reflects trees. The subject is the thing that does the reflecting. The object is the thing reflected. "Snow reflects lights," snow [subject] reflects [verb] lights [object]. That's the usual usage. As a matter of word usage, not grammar, I would have written: The snow reflected different colors from the bright lights. Bright lights everywhere made different colored reflections on the snow.

Your sentences are correct, but the original sentence is a bit strange. Lights shine while surfaces (such as mirrors) reflect. The snow could reflect the colours.

There is no difference between these two sentences. The first one is active voice and the second one is passive voice.