Add Dark Mode Support

[97115104]

Labels: good first issue, enhancement, ui/ux

Description

Add a dark mode theme to improve accessibility and user preference support.

Tasks

• Create CSS variables for dark mode colors
• Add a theme toggle button in the header
• Save theme preference to localStorage
• Update all pages to respect theme preference
• Test color contrast for accessibility

Files to modify

• /static/style.css
• /static/theme-switcher.js (new file)
• All HTML files (add theme toggle)

Expected outcome

Users can switch between light and dark themes with their preference persisted.