🌟 style: Update Chat Input Style to Match ChatGPT (ChatGPT UI)

[techwithanirudh]

Summary

Updated the Chat Input component’s style and enhanced dark mode colors for a better user experience.

Note: ⚠️ This P.R. is one of multiple smaller P.R.s split from a larger one by GPT-4o.

Desktop

Before:

After:

Mobile

Before:

After:

Change Type

• New feature (non-breaking change which adds functionality)

Testing

N/A

Test Configuration:

N/A

Checklist

• My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• I have commented in any complex areas of my code
• My changes do not introduce new warnings
• Local unit tests pass with my changes