feat: add hover color shift animation submission

[AyushPrad2907]

Pull Request Description

This PR adds a new animation submission called Hover Color Shift Animation inside submissions/examples/hover-color-shift/.

The animation creates a smooth gradient color transition on hover, providing an engaging and modern visual effect for buttons, cards, links, and promotional sections.

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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

• All changes are inside submissions/examples/hover-color-shift/
• Includes demo.html
• Includes style.css
• Includes README.md
• No changes to core/
• No changes to components/
• One feature per PR

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Feature Description

What does this add?

A hover animation that smoothly shifts background colors through a gradient transition, creating a visually appealing interactive effect.

How does a developer use it?

<button class="hover-color-shift">
  Hover Me
</button>

Why does it fit EaseMotion CSS?

The effect is easy to understand, animation-focused, and commonly used in modern UI design. It enhances interactivity while remaining lightweight and reusable.

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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

The animation is implemented using pure CSS gradients, transitions, and pseudo-elements. The demo includes multiple practical use cases to showcase how the effect can be integrated into modern interfaces.

[github-actions]

✅ Submission Validation Passed!

Great job! All required files are present.

📁 Folder: submissions/examples/hover-color-shift

Files found:

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

🚀 Next Steps:

• The 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! 🎉