Introducing Dark Mode For Desktop Devices

[Jitmisra]

Description
This PR introduces dark mode support across the website with the following changes:

• Added a dark mode toggle button with sun/moon icons in the navigation bar
• Implemented system-wide dark mode styling using Bootstrap's theme system
• The dark mode toggle is visible only on desktop/larger screens (≥992px)
• Dark mode preference persists across page reloads using localStorage
• Updated color schemes for better contrast and readability in dark mode
• Added appropriate dark mode styles for:
  • Navigation elements
  • Footer content
  • Workshop listings
  • Text and link colors
  • Background colors

Testing

• Verified dark mode toggle works across different pages
• Confirmed color contrast meets accessibility standards
• Tested persistence of theme selection
• Checked responsive behavior on different screen sizes

2025-02-25.16-02-19.mov

[mhils]

Thank you for the PR.

I'm 👎 on merging this. Implementation quibbles aside (the switch button is way too prominent), I think the added value of dark mode is generally outweighed by the increased maintenance costs over time. The screencast is a great example: The 2024 workshop announcement image looks really quite unprofessional. Fixing every future blog post image to work in both light and dark mode just generates unnecessary work.