[FEATURE] Interactive Comparison Image Slider (Before/After)

[hruthika18]

Pull Request Description

Adds an interactive before/after image comparison slider to submissions/examples/, resolving #55696. Solves the lack of a split-screen comparison component for photo-editing and UI-redesign showcases.

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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/ (e.g., submissions/examples/your-feature-name/ or submissions/docs/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 draggable before/after comparison slider that reveals a top image layer over a bottom one, using clip-path bound to a single CSS custom property.

How does a developer use it?

<div class="compare" style="--clip-offset: 50%">
  <div class="compare-frame">
    <div class="compare-layer compare-layer--before">...</div>
    <div class="compare-layer compare-layer--after">...</div>
    <div class="compare-handle"></div>
  </div>
  <input type="range" class="compare-range" min="0" max="100" value="50" />
</div>

Why does it fit EaseMotion CSS?
It keeps the interaction declarative and human-readable — one custom property (--clip-offset) drives the whole reveal, and a native range input supplies drag, touch, and keyboard support with no custom pointer-tracking JS. That matches the framework's philosophy of small, readable CSS doing the heavy lifting rather than hand-rolled animation logic.

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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

Two working instances included (photo color-grade, UI wireframe-to-redesign) to show the component works on both illustrative and flat UI content. script.js is intentionally minimal — it only mirrors the range input's value onto --clip-offset on input; no drag math or animation frame loop.

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[SAPTARSHI-coder]

✅ Submission Validation Passed!

Great job! All required files are present and valid.

📁 Folder: submissions/examples/before-after-image-slider-em

Files found:

• ✅ demo.html
• ✅ style.css
• ✅ README.md

🚀 Next Steps:

• A maintainer will review your PR
• Respond to any feedback if requested
• Once approved, your contribution will be merged!

Thank you for contributing to EaseMotion CSS! 🎉

[github-actions]

🎉 Congratulations on your PR merge, @hruthika18! 🚀

Thank you so much for your valuable contribution to EaseMotion CSS! Your code is now merged into the main branch.

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[github-actions]

🎉 Pull Request Integrated!

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