feat(components): add zero-JS ease-modal component (#251)

[bhavyabhardwaj001]

Pull Request Description

Resolves #251.

This submission introduces a highly-performant, zero-JavaScript ease-modal component. It natively handles open states, close states, and backdrop-click-to-close entirely using the browser's URL hash and the CSS :target pseudo-class.

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Type of Change

• ✨ New animation / hover effect
• 🧩 New component
• 📝 Documentation improvement
• 🐛 Bug fix in an existing submission
• Other (describe below)

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Submission Checklist

⚠️ PRs that fail this checklist will be closed without review.

• All changes are inside submissions/examples/your-feature-name/
• Includes demo.html — self-contained, opens in browser with no server
• Includes style.css — raw CSS for the proposed feature
• Includes README.md — what it does, how to use it, why it fits EaseMotion CSS
• No changes to core/
• No changes to components/
• One feature per PR (no bundled unrelated changes)

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Feature Description

What does this add?

A pristine CSS-only modal leveraging the :target selector.

How does a developer use it?

Give the .ease-modal-overlay a unique ID, and use an <a> tag pointing to that ID to open it.

<!-- Trigger -->
<a href="#my-modal" class="ease-btn ease-btn-primary">Open Modal</a>

<!-- Modal Structure -->
<div id="my-modal" class="ease-modal-overlay">
  <!-- Invisible backdrop click-to-close -->
  <a href="#" class="ease-modal-backdrop-close"></a>
  
  <div class="ease-modal-box">
    <!-- Close X button -->
    <a href="#" class="ease-modal-close">&times;</a>
    <h2>Modal Content</h2>
  </div>
</div>

Why does it fit EaseMotion CSS?

Modals are typically one of the most JS-heavy components in UI libraries, requiring event listeners for backdrop clicks and close buttons. This CSS-only implementation drastically reduces bundle size and JS execution time, perfectly aligning with the framework's CSS-first philosophy. Furthermore, it explicitly handles prefers-reduced-motion by gracefully falling back to a pure opacity fade rather than sliding/scaling in.

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Demo

• Demo added (demo.html works by opening directly in a browser)

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Browser Testing

• Chrome
• Firefox
• Edge
• Safari (optional but appreciated)

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Notes for Maintainer

I solved the "backdrop click to close" requirement without Javascript by placing a full-screen, invisible <a> tag (.ease-modal-backdrop-close) directly behind the .ease-modal-box that points to href="#". When clicked, it clears the target and naturally closes the modal!