What if we apply something similar to how primary colors work but to the elements?
With light sources, you have an additive system where red, green and blue are the primary colors. By adding them all together you get white, the Light
For printing (as we see light reflection), you have a subtractive system, where cyan, magenta and yellow are the primary colors. By adding them all together you get black, the Darkness.

The Shards are reflections of the Source after all....