Main site engineering and architecture: Pages Router, proxy middleware, content system, protected posts, API, adaptive performance tiers, gotchas.

Runtime: server.js entry, env vars, Vercel + Tencent Cloud DNSPod, COS bucket layout and version pointers, font hosting, asset publishing pipeline, telemetry, SEO and security.

Intelligent subsystems: useAdaptivePerformance four-tier controller, GEO_COUNTRY cookie and region-only UI, Hitokoto and tweet acquisition, agent collaboration conventions.

Visual system: typography and font variables, color palette and visual language, loading and route transitions, Three.js effects.