How to color a side of a CSGPolygon?

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:bust_in_silhouette: Asked By MoonMountain

I’ve never made anything in 3d before, and this is my first project. I want to make a Square-1 puzzle.

I just need a simple cube made of some shapes, and the CSGPolygon seems perfect for that.

The main thing is, I don’t know how to color the faces and sides of it. I prefer a simpler look, so I want to just color the triangles of the CSGPolygon if possible.

Sorry if this is a stupid question, I’m just really new to 3d.