Implement Dark/Light Theme Toggle with Persistence and Accessibility

[Copilot]

This PR implements a fully functional dark/light theme switcher that resolves the disabled theme toggle button and adds complete theming support to the CodeStorm Hub website.

Problem

The theme toggle button in the header was previously disabled and non-functional, lacking the necessary infrastructure for theme management, persistence, and accessibility compliance.

Solution

Implemented a comprehensive theme system using React Context API with the following key components:

Theme Context Provider (src/lib/theme-context.tsx)

• Created a centralized theme management system using React Context
• Handles theme state, localStorage persistence, and DOM class manipulation
• Provides toggleTheme, setTheme, and mounted state for proper hydration

Enhanced CSS Variables (src/app/globals.css)

• Replaced media query-based dark mode with class-based theming (.dark)
• Extended CSS custom properties for complete theme coverage
• Added enhanced shadows and improved color contrast for accessibility
• Uses Radix Colors semantic scale for consistent design

Layout Integration (src/app/layout.tsx)

• Wrapped the entire application with ThemeProvider for global theme access
• Ensures theme context is available throughout the component tree

Hook Simplification (src/hooks/use-theme.ts)

• Refactored existing hook to use the new theme context
• Maintains backward compatibility with existing API
• Cleaner separation of concerns

Features

• 🎨 Visual Themes: Complete light and dark themes with proper contrast ratios
• 💾 Persistence: Theme preference saved in localStorage and restored on page load
• ♿ Accessibility: Full keyboard navigation support (Tab + Enter) with proper ARIA labels
• ⚡ Performance: Optimized hydration handling prevents SSR/client mismatches
• 🎯 User Experience: Smooth theme transitions with immediate visual feedback

Screenshots

Light Theme

Dark Theme

Technical Details

The implementation follows React best practices and Next.js patterns:

• Client-side rendering for browser API access (localStorage, matchMedia)
• Proper hydration handling with mounted state to prevent flash of unstyled content
• CSS custom properties enable instant theme switching without re-renders
• Minimal code changes ensure compatibility with existing components

Testing

• ✅ Theme toggle functionality (mouse and keyboard interaction)
• ✅ Theme persistence across browser sessions and page refreshes
• ✅ Keyboard accessibility compliance (WCAG 2.1 AA)
• ✅ Visual completeness and contrast ratios for both themes
• ✅ No console errors or hydration warnings

The theme toggle button is now fully enabled and provides a polished dark/light mode experience for all users.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Implement Dark/Light Theme Toggle (Enable Theme Switcher)</issue_title>
<issue_description>## Summary
The theme toggle button is currently disabled and lacks functionality. Implement a fully functional dark/light mode switcher using Radix Colors and CSS custom properties, with theme persistence and accessibility compliance.

Requirements

• Implement theme context provider
• Add theme switcher component using Radix Colors
• Use CSS custom properties for theming
• Persist user preference (local storage)
• Apply theme globally across all components
• Ensure toggle is keyboard accessible

Acceptance Criteria

• Toggle button is enabled and accessible
• Theme persists across sessions
• Dark and light themes both visually complete
• All UI components respond to theme changes

---

Priority: Critical
Deadline: October 7, 2025

References

• comprehensive-audit-report.md
• technical-issues-summary.md</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #30

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[Copilot]

Pull Request Overview

This PR implements a comprehensive dark/light theme toggle system for the CodeStorm Hub website, replacing a previously disabled theme button with a fully functional theming solution. The implementation uses React Context API for state management, localStorage for persistence, and CSS custom properties for styling.

Key changes:

• Created a centralized theme management system with React Context
• Refactored existing theme hook to use the new context provider
• Updated CSS to use class-based theming instead of media queries

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/lib/theme-context.tsx	New theme context provider with state management, persistence, and DOM manipulation
src/hooks/use-theme.ts	Simplified hook that delegates to the theme context
src/app/layout.tsx	Wrapped application with ThemeProvider for global theme access
src/app/globals.css	Converted from media query-based to class-based theming with enhanced dark mode support

[Copilot]

The type assertion as Theme | null is unsafe. If localStorage contains an invalid theme value, the type assertion will succeed but the runtime check will fail. Consider using type guards or removing the assertion and relying only on the runtime validation.

Suggested change

	const stored = localStorage.getItem('theme') as Theme | null
	const stored = localStorage.getItem('theme')

[Copilot]

The localStorage.getItem() and window.matchMedia() calls should be wrapped in try-catch blocks to handle potential SecurityError exceptions in environments where these APIs are restricted (e.g., sandboxed iframes, private browsing modes).