Fixed Dark Theme Toggle Functionality (Issue #540)

[gayatridot]

📝 PR Title

Fixed Dark Theme Toggle Functionality (Issue #540)

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📌 Description

This PR resolves the bug reported in Issue #540 where the light/dark mode toggle button was non‑functional.

✅ Changes Made

• Implemented a global theme-toggle.js script that:
  • Applies dark-theme by default and switches to light-theme when toggled.
  • Stores the user’s preference in localStorage so the theme persists across all pages.
  • Updates the toggle button state (sun/moon icons and thumb position) based on the active theme.
• Updated CSS to handle .dark-theme and .light-theme classes consistently.
• Ensured the toggle button works across all pages by including the script globally.

🎯 Benefits

• Restores expected functionality of the theme toggle button.
• Provides a consistent user experience across the site.
• Remembers user preference between sessions.
• Improves accessibility and usability.

📷 Screenshot

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