Great game and loved the simple design. Btw I just wanted to ask, How did you created that Gradient Material?
Rhys (Grey Gravel) made the 2D sprites (Pillars) with the gradient already in it. The Animated sprites followed the gradient too and then I just set the background color to match the color of pillars. You can also use a Height based shader to achieve this effect.
Here is a link to the Pillar sprites
https://imgur.com/a/UiWs3qS