feat: Added a dark mode chat bubble

[Ayontikapal]

Pull Request Description

Fixes #11293
This PR adds a dark mode chat bubble in the chat-bubble-sb

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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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Do not self-merge, even if you have write access.
Maximum 2 active assigned issues per contributor — unassign extras before opening a PR.

Tip: Once you open your PR, feel free to showcase your design or component in the #showcase channel on our official Discord Server!

[github-actions]

✅ Submission Validation Passed!

Great job! All required files are present.

📁 Folder: submissions/examples/chat-bubble-sb

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! 🎉

[github-actions]

🎉 Pull Request Integrated!

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

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[github-actions]

🎉 Congratulations on your PR merge, @Ayontikapal! 🚀

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

🎮 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 💜

Thank you again, and happy coding! 💻