- Change background from #0a0a0f to #0a0a0a (matching vectry.tech + AgentLens) - Remove unused --accent-cyan and --shadow-card tokens - Add shared Vectry design aliases (surface-page, surface-card, border-default, radius-card, etc.) - Fix hardcoded #0a0a0f in layout.tsx, history/page.tsx, and mermaid-diagram.tsx