**Learning:** The brand color `#667eea` fails WCAG AA contrast (3.4:1) against white backgrounds, affecting accessibility for text headers and primary buttons.
**Action:** Replace `#667eea` with `#4f46e5` (Indigo 600) which passes WCAG AA (5.5:1) while maintaining brand identity. Update all instances including `manifest.json`.
**Learning:** This project maintains three separate dashboard implementations (`index.html`, `dashboard/index.html`, `scripts/web_dashboard.py`). UX improvements must be manually synchronized across all three to prevent feature drift between the PWA and the backend-rendered view.
**Action:** Always grep for dashboard components across these three files when implementing UI changes.
