You can check out my build thread for a lot more pictures and to see how it is done. But it's simply what is called edge lit acrylic. There is a layer in there that is clear acrylic. I frost the edge to diffuse the LED light strip that wraps around the clear acrylic, hidden behind the main black panel. There is an orange layer of acrylic that sits behind the clear acrylic. It blocks out light from going back inside where the modules mount. It also serves as a cosmetic piece when the LED lights are not on. The orange color of acrylic was chosen to match my color scheme of the sump... it has no bearing on the color outcome of the edge lighting.