feat: add slide down animation submission

[Shreeya1207]

Description

This PR adds a new submission demonstrating a Slide Down Entrance animation effect.

Added Effect

• slide-down

Files Added

• submissions/examples/ease-slide-down/demo.html
• submissions/examples/ease-slide-down/style.css
• submissions/examples/ease-slide-down/README.md

Demo

The demo showcases a smooth slide-down entrance animation where elements move from above into their final position while gradually becoming visible. The effect creates a polished and engaging content reveal experience.

Why

Slide-down entrance animations are commonly used for cards, banners, notifications, hero sections, dropdowns, and content reveals. They help guide user attention and improve perceived responsiveness while maintaining a clean and reusable implementation. This submission aligns with EaseMotion CSS's philosophy of practical, expressive, and human-readable animation utilities.

Checklist

• Added files only inside submissions/
• Included demo.html
• Included style.css
• Included README.md
• One feature per PR
• Demo works without external dependencies
• Followed contribution guidelines

[github-actions]

✅ Submission Validation Passed!

Great job! All required files are present.

📁 Folder: submissions/examples/ease-slide-down

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! 🎉