大理石底座上的逼真微缩城市立体模型

Create a photorealistic 12-K miniature city diorama on a polished white-marble base. GEOMETRY • ONE continuous **flat, horizontal spiral ramp** (nautilus-like). • Center = oldest cityscape; outer edge = newest. • No vertical stacking or helical tower; ramp height must remain level (±5 % at most). ERA TRANSITION (model chooses specific details) 1. 500 BC zone – era specific homes 2. 1000 AD zone – era specific homes and buildings 3. 1800 AD zone – era specific homes and buildings 4. 2025 AD zone – era specific homes and buildings BASE & LABEL Engrave the four dates on the marble rim in order: “500 BC → 1000 AD → 1800 AD → 2025 AD”. LIGHTING Neutral gray cyclorama; overhead **spiral** key-light that follows the flat ramp, casting radial shadows. QUALITY & HARD CONSTRAINTS Ultra-real, cinematic sharpness. NEGATIVE PROMPT: VERTICAL_HELIX • STACKED_TIERS • MISSING_LABEL • LOW_DETAIL • WRONG_RING_COUNT