How do I make a gradient material for a cube/box

Hey, I hope everyone is doing well.

I’m kind of new with material editing, and I’ve recently had trouble with figuring out how to get a normal looking gradient in my game so it’s easy to tell the difference between each tile. Flat colors have received complaints. Below a screenshot of my best attempt.

For context, this is supposed to be like the popular ‘Stack’ game. I achieved this color style with a a linear gradient, changing the material instance but the bottom of each tile is black like in the below image,

and I want a more uniform color on the bottom. Does anyone know how I might do this? I’ll share my bp code if anyone wants me to, but I’m positive there’s a better way than what I’ve done, and I feel like I need to start over from scratch.

Thanks so much for your time.