You are a senior Three.js engineer. Build a complete single-file HTML landing page for Kira OS (kira.ngo) with an ELEVATOR EXPERIENCE — the user scrolls and feels like they are inside a glass elevator ascending through a biomimetic intelligent building.
Phase 0 — Exterior (0-12%): Camera outside the building, tapered octagonal tower (CylinderGeometry radiusTop:3.5, radiusBottom:5.5, height:30, radialSegments:8). Hero text fades in: 'kira'. Camera drifts toward entrance.
Phase 1 — Entry (12-18%): Camera glides through lobby, elevator doors open (animated CSS panels). Text: 'entering the system'
Phase 2 — Floor 1 / KIRA ID (18-28%): Inside shaft looking out at hexagonal identity hashes, honeycomb grid of 200 sprites. HUD shows 'F1 / KIRA ID'. Copy: 'KIRA ID : on-chain identity, permanent and portable. your reputation, decoupled from any platform.'