🐛 [Fix] Resolve login page issue and add dark mode support

[Rajitha-20050412]

Description:
Fixed the issue where the login page was not opening and added dark mode support for the login and signup pages.
Closes #561

Type of change:

• Bug fix
• New feature
• Improvement
• Documentation update

How Has This Been Tested?

• Verified that the login modal now opens correctly when the login button is clicked.
• Tested the toggle between login and signup forms.
• Checked dark mode toggle to ensure proper styling is applied for both login and signup pages.
• Tested on multiple browsers to confirm functionality.

Screen.Recording.2025-09-21.124843.mp4

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code where necessary
• I have added tests that prove my fix is effective or that my feature works
• [x ] I have made corresponding changes to the documentation

[github-actions]

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