4 layers80 × 55 mm

Demo board
atuzlak/kicad-splitplane
Split a KiCad power layer into one continuous copper zone per voltage
2 parts2MIT
KiCad boards from 1 GitHub repository tagged “power-plane”, the most starred first; open any of them in PCBKit.

atuzlak/kicad-splitplane
Split a KiCad power layer into one continuous copper zone per voltage