Very simple snap-click box with rounded corners and a uniform wall thickness.
Optional: with screw holes and poles with ribs.
Actually just a field test while I was learning how to use OpenSCAD, inspired by sej7278 (and Pecollado) and their nice idea to use offset() for the rounded corners. :)
EDIT: updated snap-click tolerances, teardrop shape for power holes.
EDIT: configurable snap fit tolerance. My initial upload was a very tight fit.