Why Dark Mode Matters

Dark mode isn't just a trend — it reduces eye strain in low-light environments, saves battery on OLED screens, and gives users control over their experience.

Setting Up next-themes

The next-themes library is the simplest way to add theme support to a Next.js App Router project.

Installation

npm install next-themes

Theme Provider

Wrap your application in a ThemeProvider component that uses the class strategy for Tailwind CSS compatibility.

CSS Variables

Define your color tokens as CSS variables with both light and dark variants. The .dark class toggles between them.

Design Considerations

Contrast Ratios

Ensure text remains readable in both themes. WCAG guidelines recommend a minimum contrast ratio of 4.5:1 for normal text.

Image Handling

Some images may need different treatments in dark mode. Consider using CSS filters or providing separate assets.

Transitions

Add transition-colors to elements that change color between themes for a smooth switch experience.

Testing

Always test your dark mode implementation across different browsers and devices. Pay special attention to flash-of-unstyled-content (FOUC) on page load.

Implementing Dark Mode in Next.js with next-themes