Audit and fix HTML semantics across the app:
- Use <button> for actions, <a> for navigation (never the reverse)
- Use <nav>, <main>, <aside>, <header>, <footer>, <article>, <section> for page structure
- Use <h1>-<h6> in order (no skipped levels, never used just for styling)
- Use <label> linked to every form input
- Use <ul>/<ol> for lists
- Use <table> with proper <th> headers for tabular data
- Use <dialog> for modals

Ensure full keyboard accessibility:
- Every interactive element (button, link, input, select) must be reachable with Tab
- Every interactive element must be activatable with Enter or Space
- Tab order must follow visual reading order
- Focus states must be clearly visible (not just outline: none)
- Modals must trap focus inside and return focus to the trigger on close
- Add a "Skip to main content" link as the first focusable element

Check and fix color contrast across the app:
- Verify all text meets WCAG AA contrast ratios (4.5:1 for body, 3:1 for large text)
- Verify UI elements (borders, icons, focus rings) meet 3:1 contrast
- Don't rely on color alone — add icons, patterns, or text labels alongside color indicators
- Test with the browser's built-in contrast checker

Fix form accessibility:
- Every input must have a visible <label> linked via for="id" attribute
- Placeholder text is NOT a label (it disappears on focus)
- Required fields: add visual indicator AND aria-required="true"
- Add autocomplete attributes for personal data: autocomplete="email", "name", etc.

Fix image accessibility:
- Every meaningful image needs descriptive alt text (max 125 chars)
- Decorative images need alt="" (empty alt, not missing alt)
- Charts and diagrams need a text description nearby or via aria-describedby

Improve focus management and error handling:
- When a modal opens, move focus to the first interactive element inside
- When a modal closes, return focus to the button that opened it
- Trap focus inside modals (Tab shouldn't escape to the background)
- Connect error messages to inputs via aria-describedby
- When a form has errors, add aria-invalid="true" to invalid fields
- Announce dynamic content changes with aria-live="polite" (status messages) or aria-live="assertive" (errors)

Respect user motion preferences:
- Add a CSS media query: @media (prefers-reduced-motion: reduce) { * { animation: none !important; } }
- Disable autoplay on videos and carousels when reduced motion is preferred
- Keep transitions under 200ms or remove them for reduced-motion users

Run an accessibility audit:
- Run axe-core or Lighthouse accessibility audit on our main pages
- Report all violations grouped by severity (critical, serious, moderate, minor)
- Fix all critical and serious violations
- Add accessibility checks to our CI pipeline so new issues are caught automatically