docs: add expandable-accordion-menu showcase demo

[WHENKEY2007]

Pull Request Description

Submits an interactive showcase and demo for the expandable-accordion-menu component under submissions/examples/.

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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/
• 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?
Smoothly collapsing accordion menu utilizing modern CSS grid-template-rows expansion animations.

How does a developer use it?
Check the folder submissions/examples/expandable-accordion-menu/.

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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

[SAPTARSHI-coder]

✅ Submission Validation Passed!

Great job! All required files are present and valid.

📁 Folder: submissions/examples/expandable-accordion-menu

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! 🎉

[SAPTARSHI-coder]

✅ Submission Validation Passed!

Great job! All required files are present and valid.

📁 Folder: submissions/examples/expandable-accordion-menu

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, @WHENKEY2007! 🚀

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

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Thank you again, and happy coding! 💻

[github-actions]

🎉 Pull Request Integrated!

Thank you for your contribution, @WHENKEY2007! Your changes have been successfully merged into main and will be credited to your wall. 🚀

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🎮 Join our Discord Server!
We have an official Discord server for EaseMotion CSS! Join us to connect with other developers, seek help, discuss design choices, and share your creations in the showcase channel: Join the EaseMotion CSS Discord 💜