Accessibility (WCAG) - Building Inclusive Web Applications

When to use this skill

• Implementing ARIA labels, roles, and properties
• Ensuring full keyboard navigation support
• Supporting screen readers (NVDA, JAWS, VoiceOver)
• Providing text alternatives for images and media
• Managing focus and focus indicators
• Creating accessible forms with proper labels
• Building inclusive, usable UI components
• Testing with axe DevTools or similar tools
• Meeting WCAG 2.1/2.2 AA or AAA compliance
• Designing for color blindness and low vision
• Implementing skip links and landmarks
• Ensuring sufficient color contrast ratios

When to use this skill

• Designing UIs, implementing components, ensuring compliance with accessibility standards (WCAG 2.1/2.2).
• When working on related tasks or features
• During development that requires this expertise

Use when: Designing UIs, implementing components, ensuring compliance with accessibility standards (WCAG 2.1/2.2).

Core Principles (POUR)

1. Perceivable - Information available to all senses
2. Operable - Interface elements functional for all users
3. Understandable - Content and interface are clear
4. Robust - Works across technologies including assistive devices

Essential Patterns

Semantic HTML

<!-- ✅ Proper semantic structure -->
<header><nav><ul><li><a></a></li></ul></nav></header>
<main><article><h1></h1><p></p></article></main>
<footer></footer>

<!-- ❌ Div soup -->
<div class="header"><div class="nav"></div></div>

ARIA Labels & Roles

<button aria-label="Close dialog">×</button>
<nav aria-label="Main navigation"></nav>
<input aria-describedby="email-error" />
<div role="alert" aria-live="polite">Success</div>

Keyboard Navigation

function Modal({ onClose }: { onClose: () => void }) {
  useEffect(() => {
    const handleEscape = (e: KeyboardEvent) => {
      if (e.key === 'Escape') onClose();
    };
    document.addEventListener('keydown', handleEscape);
    return () => document.removeEventListener('keydown', handleEscape);
  }, [onClose]);
  
  return <div role="dialog" aria-modal="true" tabIndex={-1}>...</div>;
}

Focus Management

const firstFocusableElement = dialogRef.current?.querySelectorAll(
  'button, [href], input, select, textarea, [tabindex]:not([tabindex="-1"])'
)[0];
firstFocusableElement?.focus();

Resources

• WCAG 2.1 Guidelines
• MDN Accessibility
• axe DevTools