html · chain · relay · step 047 of 64
offline render, Chrome 154, light scheme, 2 s of virtual time
This page calls Math.random or the clock, so a live run can differ from this render.
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<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8">
<meta http-equiv="content-security-policy" content="default-src 'none'; script-src 'unsafe-inline'; style-src 'unsafe-inline'; img-src data:; base-uri 'none'; form-action 'none'">
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<meta name="description" content="A well-structured, accessible HTML5 document demonstrating modern best practices for semantic markup and inclusive design.">
<meta name="author" content="ksmith@centricle.com">
<meta name="color-scheme" content="light dark">
<meta name="theme-color" content="#ffffff" media="(prefers-color-scheme: light)">
<meta name="theme-color" content="#121212" media="(prefers-color-scheme: dark)">
<meta property="og:title" content="Welcome - Accessible HTML5 Guide">
<meta property="og:description" content="Modern HTML5 demonstrating accessibility, semantic markup, and responsive design.">
<meta property="og:type" content="website">
<meta name="twitter:card" content="summary">
<title>Welcome - Accessible HTML5 Guide</title>
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button,
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caption {
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td {
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</style>
</head>
<body>
<a class="skip-link" href="#main">Skip to content</a>
<header id="top">
<div class="header-bar">
<h1>Welcome</h1>
<button id="theme-toggle" class="theme-toggle" type="button" aria-label="Switch to dark mode" title="Switch to dark mode" hidden>🌙</button>
</div>
<nav aria-label="Page sections">
<ul>
<li><a href="#features">Features</a></li>
<li><a href="#examples">Examples</a></li>
<li><a href="#accessibility">Accessibility</a></li>
<li><a href="#resources">Resources</a></li>
</ul>
</nav>
</header>
<main id="main" tabindex="-1">
<section aria-label="Introduction">
<p>This is a well-structured, accessible HTML5 document demonstrating modern best practices for semantic markup and inclusive design.</p>
<p>
It uses semantic landmarks, a skip link for keyboard navigation,
and CSS that adapts to your light or dark mode preference.
</p>
<p>
Text and link colors meet WCAG AA contrast in both themes, type scales
with your browser's font size, and motion respects your system settings.
</p>
</section>
<section aria-labelledby="features">
<h2 id="features">Features</h2>
<ul>
<li>Semantic HTML structure with proper landmarks</li>
<li>Keyboard accessible navigation and focus management</li>
<li>Dark mode support with custom color schemes</li>
<li>Responsive typography using modern CSS</li>
<li>Print-friendly styles for better readability</li>
<li>WCAG AA contrast compliance in all color modes</li>
</ul>
</section>
<section aria-labelledby="examples">
<h2 id="examples">Examples</h2>
<article class="card">
<h3>Component Cards</h3>
<p>Card components are useful for organizing related content. They include a subtle border and padding for visual separation.</p>
<a class="button" href="#resources">Learn more<span class="visually-hidden"> about accessibility resources</span></a>
</article>
<article class="card">
<h3>Interactive Elements</h3>
<p>Buttons and links are fully accessible with clear focus states. All interactive elements include visible focus indicators and proper ARIA labels.</p>
<p><strong>Keyboard navigation:</strong> Use <kbd>Tab</kbd> to move forward, <kbd>Shift</kbd>+<kbd>Tab</kbd> to move backward, and <kbd>Enter</kbd> to activate.</p>
</article>
<article class="card">
<h3>Accessible Form</h3>
<form id="contact-form" novalidate>
<p class="form-hint">Fields marked * are required.</p>
<div class="field">
<label for="email">Email <span aria-hidden="true">*</span></label>
<input type="email" id="email" name="email" autocomplete="email" inputmode="email" spellcheck="false" autocapitalize="none" required aria-describedby="email-help">
<span id="email-error" class="error-message"></span>
<small id="email-help" class="form-hint">For example, name@example.com</small>
</div>
<div class="field">
<label for="message">Message</label>
<textarea id="message" name="message" rows="4" maxlength="2000" aria-describedby="message-help"></textarea>
<small id="message-help" class="form-hint">Up to 2,000 characters. <span id="message-count">2,000</span> remaining.</small>
</div>
<button type="submit">Send message</button>
<p id="form-status" role="status"></p>
</form>
</article>
<article class="card">
<h3>Live Region Example</h3>
<p>Click the button to announce a message using a live region. This demonstrates how screen readers are notified of dynamic updates.</p>
<button id="announce" type="button">Announce message</button>
<div class="live-region" aria-live="polite" aria-atomic="true">
<span id="live-message"></span>
</div>
</article>
<article class="card">
<h3>Interactive Counter</h3>
<p>This counter demonstrates state management and ARIA live regions for accessible dynamic content.</p>
<div class="counter">
<button id="decrease" type="button" aria-label="Decrease count by 1">−</button>
<output id="count" aria-live="off">0</output>
<button id="increase" type="button" aria-label="Increase count by 1">+</button>
<button id="reset" type="button" aria-label="Reset count to zero">Reset</button>
</div>
<div class="live-region" aria-live="polite" aria-atomic="true">
<span id="count-message"></span>
</div>
</article>
</section>
<section aria-labelledby="accessibility">
<h2 id="accessibility">Accessibility Features</h2>
<article class="card">
<h3>Data Table Example</h3>
<p>Accessible tables have proper headers, captions, and semantic structure for screen readers.</p>
<table>
<caption>Browser compatibility for modern features</caption>
<thead>
<tr>
<th scope="col">Feature</th>
<th scope="col">Chrome</th>
<th scope="col">Firefox</th>
<th scope="col">Safari</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">CSS Grid</th>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
</tr>
<tr>
<th scope="row">CSS Variables</th>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
</tr>
<tr>
<th scope="row">Aspect Ratio</th>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
<td><span aria-hidden="true">✓</span><span class="visually-hidden">Supported</span></td>
</tr>
</tbody>
</table>
</article>
</section>
<section aria-labelledby="resources">
<h2 id="resources">Resources</h2>
<p>Want to learn more about web accessibility and semantic HTML? Check out these resources:</p>
<ul>
<li><a href="https://www.w3.org/WAI/WCAG22/quickref/" target="_blank" rel="noopener noreferrer">WCAG 2.2 Quick Reference<span class="visually-hidden"> (opens in new tab)</span></a></li>
<li><a href="https://html.spec.whatwg.org/" target="_blank" rel="noopener noreferrer">HTML Living Standard<span class="visually-hidden"> (opens in new tab)</span></a></li>
<li><a href="https://www.a11y-101.com/" target="_blank" rel="noopener noreferrer">A11y 101<span class="visually-hidden"> (opens in new tab)</span></a></li>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/Accessibility" target="_blank" rel="noopener noreferrer">MDN Web Accessibility<span class="visually-hidden"> (opens in new tab)</span></a></li>
</ul>
</section>
</main>
<footer>
<nav aria-label="Footer links">
<ul>
<li><a href="#top">Back to top</a></li>
<li><a href="https://github.com" target="_blank" rel="noopener noreferrer">GitHub<span class="visually-hidden"> (opens in new tab)</span></a></li>
</ul>
</nav>
<p><small>© <span id="copyright-year">2026</span>. All rights reserved.</small></p>
</footer>
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emailInput.addEventListener('blur', () => {
if (emailInput.value || emailInput.hasAttribute('aria-invalid')) {
validateEmail();
}
});
emailInput.addEventListener('input', () => {
if (emailInput.hasAttribute('aria-invalid')) {
validateEmail();
}
});
contactForm.addEventListener('input', () => {
formStatus.textContent = '';
});
contactForm.addEventListener('submit', (event) => {
event.preventDefault();
formStatus.textContent = '';
if (!validateEmail()) {
emailInput.focus();
return;
}
contactForm.reset();
setEmailError('');
updateMessageCount();
setTimeout(() => {
formStatus.textContent = "Thanks! This is a demo, so nothing was sent.";
}, 100);
});
}
</script>
</body>
</html>
what changed from step 046
Nothing. The file is byte-identical to step 046.
What the model said
This is already a very polished, comprehensive accessible HTML5 demo — it covers dark mode, focus management, ARIA live regions, form validation, print styles, forced-colors, reduced-motion, etc. Since it's already high quality, could you tell me what angle you want improved? For example: - **SEO/social meta** (add `og:image`, `og:url`, canonical link) - **Performance** (inline CSS/JS could be split into external cached files) - **Accessibility polish** (e.g., counter buttons could clamp/disable at limits, better labeling) - **Code quality** (dedupe repeated theme CSS variables between the two dark-mode blocks at lines 51-80) - Something else specific you noticed One thing I did spot as a genuine cleanup opportunity: the dark theme CSS variables are duplicated verbatim in two places (the `prefers-color-scheme: dark` block and the `[data-theme="dark"]` block, lines 51-80) — that could be merged to avoid maintaining two copies. Want me to fix that, or focus elsewhere?