vulk-accessibilitylisted

# Accessibility -- Essential Patterns 1. **Semantic HTML:** Use correct elements (nav, main, section, article, aside, footer, header) 2. **Headings:** One h1 per page, then h2 -> h3 -> h4 in order. Never skip levels 3. **Images:** Always alt text. Decorative images: alt="" 4. **Buttons vs Links:** Button for actions, anchor for navigation. Never div with onClick 5. **Focus:** All interactive elements must be keyboard accessible with visible focus ring 6. **Color contrast:** 4.5:1 minimum for text, 3:1 for large text 7. **Forms:** Every input needs a label (visible or sr-only). Error messages linked with aria-describedby 8. **Reduced motion:** Wrap animations in `@media (prefers-reduced-motion: no-preference)`