A colossal subterranean glacier megacity carved into a massive frozen canyon, towering ice spires with bioluminescent core lighting piercing through crystalline walls, suspended transparent bubble districts enclosing floating aurora gardens, sleek ice-craft gliding between frozen waterfalls glowing soft violet, tiny polar architects dwarfed by mountain-sized ice cathedrals, deep arctic blue and electric aurora purple palette with soft polar light filtering through endless ice layers, epic upward shot from frozen canyon floor with tiny silhouetted explorers on illuminated platform emphasizes impossible glacial engineering scale, photorealistic, cinematic depth of field