Sidewalk Cellar Hatch

Sidewalk cellar hatch, 1.6x1.2m twin steel doors in a low frame sitting 0.1m proud of the pavement, diamond tread as shallow relief; knobs for door state (closed, one leaf open, both open) and a metal colorway.

风格：low-poly, flat-shaded vertex colors, no textures, single shared material, so any set of these merges to one draw call; shares palette and scale with its kit