- Dark mode toggle (●/○) in desktop + mobile header nav
- ThemeProvider wired in layout.tsx (class-based, light default)
- Header scroll-glass uses CSS color-mix for dark-mode correctness
- PortalShell main gets id="main-content" for skip-link target
- Portal order table: copy order ID to clipboard with toast confirmation
- Admin page: toast success/error on status advance
- Skip-to-content link in layout.tsx (sr-only, visible on keyboard focus)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>