Create a detailed 3D model of a Cobra-style enemy base inspired by classic 1980s G.I. Joe playsets. The design should feel sinister and high-tech, built into a mountain or volcanic cliffside with angular architecture, snake or fang motifs, and dark metallic surfaces. Include a central command tower with Cobra insignia area, landing pad for jets or helicopters, hangars for vehicles, radar dishes, security turrets, blast doors, and modular walkways. The base should be segmented into modular sections for easy 3D printing and assembly, scaled for 1:18 action figures. Style keywords: Cobra base, villain fortress, mountain lair, modular playset, G.I. Joe style, high detail, STL-ready, optimized for FDM printing.