Feat: Improve UI Design of GitHub Campus Expert Screen

### Describe the feature

## Description
The current screen works properly, but the UI can be improved to make it look cleaner and more modern.
Some sections have uneven spacing, large text blocks, and inconsistent button styling, which affects the overall user experience.

## Proposed Solution
- Improve spacing and padding between sections.
- Make text easier to read with better typography.
- Improve button design and alignment.
- Add smoother card corners and better styling.
- Improve overall visual balance on mobile screens.
- Make the layout look more modern and attractive.

## Expected Outcome
- Cleaner and more professional UI.
- Better readability and user engagement.
- Improved mobile viewing experience.
- More visually consistent design across components.

## Additional Context
This issue focuses only on improving the UI/UX of the screen without changing its functionality.

### Add ScreenShots

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### Record

- [x] I agree to follow this project's Code of Conduct
- [ ] I'm a GSSOC'24 contributor
- [x] I want to work on this issue