Accessibility Checker Skill
This skill performs comprehensive CSS accessibility audits based on WCAG 2.2 guidelines. I'll identify issues and provide specific, actionable fixes to make your styles more accessible.
What I Check
Visual Accessibility
- Color contrast ratios (text, UI components)
- Text sizing and readability
- Focus indicators
- Visual hierarchy
- Spacing and target sizes
Motion & Animation
- Reduced motion support
- Animation safety (no seizure triggers)
- Auto-playing content
- Parallax effects
Interaction
- Keyboard navigation
- Focus management
- Interactive element states
- Touch target sizes
Screen Readers
- Visually hidden but accessible content
- Display/visibility usage
- Content order
- Skip links
WCAG 2.2 Guidelines I Follow
Level A (Must Have)
- 1.4.1: Color not sole indicator
- 2.1.1: Keyboard accessible
- 2.4.1: Skip navigation
- 3.2.1: Consistent on focus
Level AA (Should Have)
- 1.4.3: Contrast minimum (4.5:1)
- 1.4.11: Non-text contrast (3:1)
- 2.4.7: Focus visible
- 2.5.5: Target size (44x44px)
Level AAA (Best Practice)
- 1.4.6: Contrast enhanced (7:1)
- 1.4.8: Visual presentation
- 2.4.8: Location indication
Common Issues & Fixes
1. Missing Focus Indicators
❌ Problem
/* Removes default focus outline */
button:focus {
outline: none;
}
/* No visible focus indicator */
.link:focus {
text-decoration: underline;
}
✓ Solution
/* Clear, visible focus indicator */
button:focus-visible {
outline: 2px solid #0066cc;
outline-offset: 2px;
}
/* High contrast focus ring */
.link:focus-visible {
outline: 2px solid currentColor;
outline-offset: 4px;
text-decoration: underline;
}
/* Fallback for browsers without :focus-visible */
button:focus {
outline: 2px solid #0066cc;
outline-offset: 2px;
}
button:focus:not(:focus-visible) {
outline: none;
}
2. Insufficient Color Contrast
❌ Problem
/* 2.85:1 contrast - fails AA */
.text-muted {
color: #999999;
background: #ffffff;
}
/* 3.2:1 contrast - fails AA for normal text */
.button {
color: #3b82f6;
background: #ffffff;
}
✓ Solution
/* 7.03:1 contrast - passes AAA */
.text-muted {
color: #666666;
background: #ffffff;
}
/* 7.02:1 contrast - passes AAA */
.button {
color: #2563eb;
background: #ffffff;
}
/* Alternative: Use for large text only */
.large-text {
font-size: 18px; /* or 14px bold */
color: #3b82f6; /* 4.52:1 - passes AA for large text */
}
3. Tiny Touch Targets
❌ Problem
/* 20x20px - too small */
.icon-button {
width: 20px;
height: 20px;
padding: 0;
}
✓ Solution
/* 44x44px - meets WCAG 2.5.5 */
.icon-button {
width: 44px;
height: 44px;
padding: 12px; /* 20px icon + 12px padding each side */
}
/* Or use minimum size */
.icon-button {
min-width: 44px;
min-height: 44px;
padding: 0.75rem;
}
4. No Reduced Motion Support
❌ Problem
/* Animated without considering preferences */
.animated {
animation: spin 2s infinite;
transition: all 0.5s ease;
}
✓ Solution
/* Respects user preferences */
.animated {
animation: spin 2s infinite;
transition: all 0.5s ease;
}
@media (prefers-reduced-motion: reduce) {
.animated {
animation-duration: 0.01ms;
animation-iteration-count: 1;
transition-duration: 0.01ms;
}
}
/* Or completely remove animations */
@media (prefers-reduced-motion: reduce) {
*,
*::before,
*::after {
animation-play-state: paused !important;
transition-duration: 0.01ms !important;
}
}
5. Hidden from Screen Readers
❌ Problem
/* Hidden from everyone including screen readers */
.error-message {
display: none;
}
.announcement {
visibility: hidden;
}
✓ Solution
/* Visually hidden but accessible to screen readers */
.sr-only {
position: absolute;
width: 1px;
height: 1px;
padding: 0;
margin: -1px;
overflow: hidden;
clip: rect(0, 0, 0, 0);
white-space: nowrap;
border-width: 0;
}
/* Hidden until shown (keeps in DOM) */
.error-message {
position: absolute;
left: -9999px;
opacity: 0;
}
.error-message.visible {
position: static;
opacity: 1;
}
6. Small Text
❌ Problem
/* 10px - too small to read */
.caption {
font-size: 10px;
}
/* Fixed pixel sizes don't scale */
body {
font-size: 14px;
}
✓ Solution
/* Minimum 12px, uses relative units */
.caption {
font-size: 0.75rem; /* 12px if root is 16px */
}
/* Uses relative units for scalability */
body {
font-size: 1rem; /* 16px default, scales with user preferences */
}
.small {
font-size: 0.875rem; /* 14px */
}
/* Or use clamp for fluid sizing */
body {
font-size: clamp(1rem, 2vw, 1.125rem);
}
7. Insufficient Line Height
❌ Problem
/* 1.1 line height - too tight */
.text {
line-height: 1.1;
}
✓ Solution
/* 1.5 line height - WCAG recommendation */
.text {
line-height: 1.5;
}
/* Adjust for different text sizes */
.heading {
line-height: 1.2; /* Tighter for large text */
}
.body {
line-height: 1.5; /* Normal for body text */
}
.caption {
line-height: 1.4; /* Slightly tighter for small text */
}
8. CSS-Only Interactions
❌ Problem
/* Hover-only dropdown - not keyboard accessible */
.nav-item:hover .dropdown {
display: block;
}
/* CSS-only toggle - not accessible */
#toggle:checked + .content {
display: block;
}
✓ Solution
/* Keyboard accessible dropdown */
.nav-item:hover .dropdown,
.nav-item:focus-within .dropdown {
display: block;
}
/* Or better: use JavaScript for complex interactions */
/* For toggle, ensure keyboard access */
.toggle-button:focus + .content,
.toggle-button[aria-expanded="true"] + .content {
display: block;
}
Accessibility Audit Checklist
Color & Contrast
- Text has 4.5:1 contrast (AA) or 7:1 (AAA)
- Large text has 3:1 contrast (AA) or 4.5:1 (AAA)
- UI components have 3:1 contrast
- Focus indicators have 3:1 contrast
- Information not conveyed by color alone
Typography
- Base font size at least 16px
- Line height at least 1.5 for body text
- Text can be resized to 200% without loss
- Max line length 70-80 characters
- Sufficient letter and word spacing
Focus & Keyboard
- All interactive elements keyboard accessible
- Visible focus indicators on all elements
- Focus order follows logical reading order
- No keyboard traps
- Skip navigation links available
Touch & Interaction
- Touch targets at least 44x44px
- Adequate spacing between clickable elements
- Hover states also have focus states
- No hover-only interactions
Motion & Animation
- Respects prefers-reduced-motion
- No auto-playing animations
- No flashing/strobing (3+ times per second)
- Animations can be paused
Screen Readers
- Important content not hidden with display:none
- Decorative images hidden with CSS
- Content order makes sense
- Visually hidden text uses proper technique
Complete Accessible Component Example
/* Accessible button component */
.button {
/* Size & spacing */
min-width: 44px;
min-height: 44px;
padding: 0.75rem 1.5rem;
font-size: 1rem; /* 16px */
/* Contrast */
background: #2563eb; /* 7.02:1 on white */
color: white; /* 9.52:1 on button bg */
border: 2px solid transparent;
/* Typography */
font-weight: 600;
line-height: 1;
text-align: center;
/* Visual */
border-radius: 0.375rem;
cursor: pointer;
transition: all 0.2s ease;
}
/* Hover state */
.button:hover {
background: #1d4ed8; /* Darker, higher contrast */
transform: translateY(-1px);
}
/* Focus state */
.button:focus-visible {
outline: 2px solid #0066cc;
outline-offset: 2px;
}
/* Active state */
.button:active {
transform: translateY(0);
}
/* Disabled state */
.button:disabled {
background: #93c5fd;
color: #1e40af;
cursor: not-allowed;
opacity: 0.7;
}
/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
.button {
transition-duration: 0.01ms;
}
.button:hover {
transform: none;
}
}
/* High contrast mode */
@media (prefers-contrast: high) {
.button {
border-color: currentColor;
}
}
Testing Tools I Recommend
- Chrome DevTools - Lighthouse accessibility audit
- axe DevTools - Browser extension for accessibility testing
- WAVE - Web accessibility evaluation tool
- Color Contrast Analyzer - Desktop tool for contrast checking
- Keyboard testing - Navigate with Tab, Arrow keys, Enter, Escape
- Screen readers - NVDA (Windows), JAWS (Windows), VoiceOver (Mac/iOS)
Example Usage
You: "Audit this button for accessibility issues"
.button {
font-size: 12px;
padding: 5px 10px;
color: #999;
background: white;
border: 1px solid #ccc;
}
.button:focus {
outline: none;
}
I'll respond:
Issues Found:
-
🔴 CRITICAL: No focus indicator
- WCAG 2.4.7 (Level AA)
- Fix: Add visible outline on :focus-visible
-
🔴 CRITICAL: Insufficient contrast
- Color #999 on white = 2.85:1 (fails 4.5:1 requirement)
- WCAG 1.4.3 (Level AA)
- Fix: Use #666 for 5.74:1 contrast
-
🟠 IMPORTANT: Small touch target
- 25x18px (estimated)
- WCAG 2.5.5 recommends 44x44px
- Fix: Increase padding
-
🟠 IMPORTANT: Small text size
- 12px may be difficult to read
- Fix: Use at least 14px (0.875rem) or 16px (1rem)
Corrected Code:
.button {
/* Size */
min-width: 44px;
min-height: 44px;
padding: 0.75rem 1.5rem;
/* Typography */
font-size: 1rem; /* 16px */
font-weight: 500;
/* Colors - AAA compliant */
color: #1f2937; /* 14.07:1 on white */
background: white;
border: 2px solid #6b7280; /* 5.77:1 on white */
/* Interaction */
cursor: pointer;
transition: all 0.2s ease;
}
.button:hover {
border-color: #374151;
background: #f9fafb;
}
.button:focus-visible {
outline: 2px solid #2563eb;
outline-offset: 2px;
}
@media (prefers-reduced-motion: reduce) {
.button {
transition-duration: 0.01ms;
}
}
Just Ask!
Request an accessibility audit:
- "Check this CSS for accessibility issues"
- "Audit my button styles"
- "Review focus indicators"
- "Check color contrast"
- "Verify WCAG compliance"
I'll identify problems and provide fixes!