fix: resolve roadmap module hover visibility issue in Light Theme

[AradhyaRay05]

Pull Request Summary

Fixes #305

This PR resolves the Roadmap module hover visibility issue in Light Theme. Some roadmap module cards/items became visually unclear or appeared blank on hover due to styling and contrast inconsistencies. The update improves readability and ensures a consistent hover experience in Light Theme while preserving Dark Theme behavior.

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Changes Introduced

• Fixed hover visibility issue in Roadmap module cards/items for Light Theme
• Updated styling in roadmap_assets/css/sub-roadmap.css to improve contrast and readability
• Preserved existing Dark Theme behavior without regressions

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Screenshots / Demo (for UI changes)

Before	After

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Checklist

Please ensure the following before requesting review:

• Code follows project conventions and best practices.
• Feature or fix works correctly on both mobile and desktop.
• No new console errors or accessibility regressions.
• Documentation updated if applicable.
• Visuals attached for UI-related updates.

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Additional Notes

This fix is limited to hover styling improvements for Roadmap module cards/items in Light Theme and does not affect existing functionality or Dark Theme behavior.

[github-actions]

📥 Pull Request Received

Thank you for your contribution to College Daddy. Your pull request has been received and is currently under review.

🔗 Linked Issues

• [Bug]: Roadmap module cards become blank on hover in Light Theme #305: [Bug]: Roadmap module cards become blank on hover in Light Theme

✅ Pre-Merge Checklist

Please ensure the following requirements are met:

• Changes adhere to contribution guidelines
• Related issues are referenced in description
• All changes tested and verified locally
• Code follows project standards

👤 Reviewer Assigned

@mugenkyou has been assigned to review this pull request.

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Our team will review your submission shortly. We appreciate your effort in improving the platform for students.

[github-actions]

🎉 Pull Request Merged Successfully

Contributor: @AradhyaRay05

Your pull request has been successfully merged into the main codebase. Thank you for your valuable contribution to College Daddy.

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