new skill web-coder (#881)

* new skill web-coder * codespellrc: add aNULL HTTPS config cipher string * Apply suggestions from code review Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> * Apply suggestions from code review * Apply suggestion from @jhauga --------- Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
2026-03-13 12:45:13 +00:00 · 2026-03-05 05:43:04 -05:00
parent abcca71546
commit 8fedf95507
19 changed files with 9073 additions and 1 deletions
--- a/skills/web-coder/references/accessibility.md
+++ b/skills/web-coder/references/accessibility.md
@@ -0,0 +1,346 @@
+# Accessibility Reference
+
+Web accessibility ensures content is usable by everyone, including people with disabilities.
+
+## WCAG (Web Content Accessibility Guidelines)
+
+### Levels
+- **A**: Minimum level
+- **AA**: Standard target (legal requirement in many jurisdictions)
+- **AAA**: Enhanced accessibility
+
+### Four Principles (POUR)
+
+1. **Perceivable**: Information presented in ways users can perceive
+2. **Operable**: UI components and navigation are operable
+3. **Understandable**: Information and UI operation is understandable
+4. **Robust**: Content works with current and future technologies
+
+## ARIA (Accessible Rich Internet Applications)
+
+### ARIA Roles
+
+```html
+<!-- Landmark roles -->
+<nav role="navigation">
+<main role="main">
+<aside role="complementary">
+<footer role="contentinfo">
+
+<!-- Widget roles -->
+<div role="button" tabindex="0">Click me</div>
+<div role="tab" aria-selected="true">Tab 1</div>
+<div role="dialog" aria-labelledby="dialogTitle">
+
+<!-- Document structure -->
+<div role="list">
+  <div role="listitem">Item 1</div>
+</div>
+```
+
+### ARIA Attributes
+
+```html
+<!-- States -->
+<button aria-pressed="true">Toggle</button>
+<input aria-invalid="true" aria-errormessage="error1">
+<div aria-expanded="false" aria-controls="menu">Menu</div>
+
+<!-- Properties -->
+<img alt="" aria-hidden="true">
+<input aria-label="Search" type="search">
+<dialog aria-labelledby="title" aria-describedby="desc">
+  <h2 id="title">Dialog Title</h2>
+  <p id="desc">Description</p>
+</dialog>
+
+<!-- Relationships -->
+<label id="label1" for="input1">Name:</label>
+<input id="input1" aria-labelledby="label1">
+
+<!-- Live regions -->
+<div aria-live="polite" aria-atomic="true">
+  Status updated
+</div>
+```
+
+## Keyboard Navigation
+
+### Tab Order
+
+```html
+<!-- Natural tab order -->
+<button>First</button>
+<button>Second</button>
+
+<!-- Custom tab order (avoid if possible) -->
+<button tabindex="1">First</button>
+<button tabindex="2">Second</button>
+
+<!-- Programmatically focusable  (not in tab order) -->
+<div tabindex="-1">Not in tab order</div>
+
+<!-- In tab order -->
+<div tabindex="0" role="button">Custom button</div>
+```
+
+### Keyboard Events
+
+```javascript
+element.addEventListener('keydown', (e) => {
+  switch(e.key) {
+    case 'Enter':
+    case ' ': // Space
+      // Activate
+      break;
+    case 'Escape':
+      // Close/cancel
+      break;
+    case 'ArrowUp':
+    case 'ArrowDown':
+    case 'ArrowLeft':
+    case 'ArrowRight':
+      // Navigate
+      break;
+  }
+});
+```
+
+## Semantic HTML
+
+```html
+<!-- ✅ Good: semantic elements -->
+<nav aria-label="Main navigation">
+  <ul>
+    <li><a href="/">Home</a></li>
+  </ul>
+</nav>
+
+<!-- ❌ Bad: non-semantic -->
+<div class="nav">
+  <div><a href="/">Home</a></div>
+</div>
+
+<!-- ✅ Good: proper headings hierarchy -->
+<h1>Page Title</h1>
+  <h2>Section</h2>
+    <h3>Subsection</h3>
+
+<!-- ❌ Bad: skipping levels -->
+<h1>Page Title</h1>
+  <h3>Skipped h2</h3>
+```
+
+## Forms Accessibility
+
+```html
+<form>
+  <!-- Labels -->
+  <label for="name">Name:</label>
+  <input type="text" id="name" name="name" required aria-required="true">
+  
+  <!-- Error messages -->
+  <input
+    type="email"
+    id="email"
+    aria-invalid="true"
+    aria-describedby="email-error">
+  <span id="email-error" role="alert">
+    Please enter a valid email
+  </span>
+  
+  <!-- Fieldset for groups -->
+  <fieldset>
+    <legend>Choose an option</legend>
+    <label>
+      <input type="radio" name="option" value="a">
+      Option A
+    </label>
+    <label>
+      <input type="radio" name="option" value="b">
+      Option B
+    </label>
+  </fieldset>
+  
+  <!-- Help text -->
+  <label for="password">Password:</label>
+  <input
+    type="password"
+    id="password"
+    aria-describedby="password-help">
+  <span id="password-help">
+    Must be at least 8 characters
+  </span>
+</form>
+```
+
+## Images and Media
+
+```html
+<!-- Informative image -->
+<img src="chart.png" alt="Sales increased 50% in Q1">
+
+<!-- Decorative image -->
+<img src="decorative.png" alt="" role="presentation">
+
+<!-- Complex image -->
+<figure>
+  <img src="data-viz.png" alt="Sales data visualization">
+  <figcaption>
+    Detailed description of the data...
+  </figcaption>
+</figure>
+
+<!-- Video with captions -->
+<video controls>
+  <source src="video.mp4" type="video/mp4">
+  <track kind="captions" src="captions.vtt" srclang="en" label="English">
+</video>
+```
+
+## Color and Contrast
+
+### WCAG Requirements
+
+- **Level AA**: 4.5:1 for normal text, 3:1 for large text
+- **Level AAA**: 7:1 for normal text, 4.5:1 for large text
+
+```css
+/* ✅ Good contrast */
+.text {
+  color: #000; /* Black */
+  background: #fff; /* White */
+  /* Contrast: 21:1 */
+}
+
+/* Don't rely on color alone */
+.error {
+  color: red;
+  /* ✅ Also use icon or text */
+  &::before {
+    content: '⚠ ';
+  }
+}
+```
+
+## Screen Readers
+
+### Best Practices
+
+```html
+<!-- Skip links for navigation -->
+<a href="#main-content" class="skip-link">
+  Skip to main content
+</a>
+
+<!-- Accessible headings -->
+<h1>Main heading (only one)</h1>
+
+<!-- Descriptive links -->
+<!-- ❌ Bad -->
+<a href="/article">Read more</a>
+
+<!-- ✅ Good -->
+<a href="/article">Read more about accessibility</a>
+
+<!-- Hidden content (screen reader only) -->
+<span class="sr-only">
+  Additional context for screen readers
+</span>
+```
+
+```css
+/* Screen reader only class */
+.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;
+}
+```
+
+## Focus Management
+
+```css
+/* Visible focus indicator */
+:focus {
+  outline: 2px solid #005fcc;
+  outline-offset: 2px;
+}
+
+/* Don't remove focus entirely */
+/* ❌ Bad */
+:focus {
+  outline: none;
+}
+
+/* ✅ Good: custom focus style */
+:focus {
+  outline: none;
+  box-shadow: 0 0 0 3px rgba(0, 95, 204, 0.5);
+}
+```
+
+```javascript
+// Focus management in modal
+function openModal() {
+  modal.showModal();
+  modal.querySelector('button').focus();
+  
+  // Trap focus
+  modal.addEventListener('keydown', (e) => {
+    if (e.key === 'Tab') {
+      trapFocus(e, modal);
+    }
+  });
+}
+```
+
+## Testing Tools
+
+- **axe DevTools**: Browser extension
+- **WAVE**: Web accessibility evaluation tool
+- **NVDA**: Screen reader (Windows)
+- **JAWS**: Screen reader (Windows)
+- **VoiceOver**: Screen reader (macOS/iOS)
+- **Lighthouse**: Automated audits
+
+## Checklist
+
+- [ ] Semantic HTML used
+- [ ] All images have alt text
+- [ ] Color contrast meets WCAG AA
+- [ ] Keyboard navigation works
+- [ ] Focus indicators visible
+- [ ] Forms have labels
+- [ ] Heading hierarchy correct
+- [ ] ARIA used appropriately
+- [ ] Screen reader tested
+- [ ] No keyboard traps
+
+## Glossary Terms
+
+**Key Terms Covered**:
+- Accessibility
+- Accessibility tree
+- Accessible description
+- Accessible name
+- ARIA
+- ATAG
+- Boolean attribute (ARIA)
+- Screen reader
+- UAAG
+- WAI
+- WCAG
+
+## Additional Resources
+
+- [WCAG 2.1 Guidelines](https://www.w3.org/WAI/WCAG21/quickref/)
+- [MDN Accessibility](https://developer.mozilla.org/en-US/docs/Web/Accessibility)
+- [WebAIM](https://webaim.org/)
+- [A11y Project](https://www.a11yproject.com/)