Virtual Lab navigation inconsistency and duplicated Chemistry URL

[chinnu8055]

The Virtual Lab section has inconsistent navigation and routing:

• Virtual Lab home page shows Physics labs, but Physics does not have a dedicated page like Chemistry.
• Clicking Physics opens a dropdown instead of a subject page, unlike Chemistry.
• Chemistry URL contains duplicated path: /virtual_lab/virtual_lab/chemistry/
• Physics dropdown menu gets hidden behind content when a lab is open.

[github-actions]

👋 Hi @chinnu8055, thank you for your interest in contributing!

We do not accept issues from external contributors. Instead, please open a Pull Request directly with your proposed changes.

If you have a bug fix, new feature, or improvement in mind, feel free to fork the repository and submit a PR — we'd love to review it! 🚀