Dark Mode Tailwind and Next.js 13

Dark mode has become increasingly popular in recent years, and many websites now offer a dark mode option for their users. In this tutorial, we will walk through how to implement a dark mode switch using Tailwind and Next.js 13.

Prerequisites

Before we get started, make sure you have the following installed:

Node.js
Next.js 13
Tailwind CSS
npm install next-themes or yarn add next-themes
npm install @heroicons/react

Set up Tailwind CSS

First, let's set up Tailwind CSS in our project. Install Tailwind and its dependencies using the following command:

    pnpm install -D tailwindcss@latest postcss@latest autoprefixer@latest

Next, create a configuration file for Tailwind using the following command:

    npx tailwindcss init -p

This will create a tailwind.config.js file in your project root.

In your postcss.config.js file, add the following configuration:

module.exports = {
	content: [
		"./pages/**/*.{js,ts,jsx,tsx}",
		"./components/**/*.{js,ts,jsx,tsx}",
		"./app/**/*.{js,ts,jsx,tsx}",
	],
	darkMode: "class",
	theme: {},
	plugins: [],
}

Using next-themes

In the layout.tsx file, wrap your component with the Provider from next-themes. Set the attribute prop to class to allow the library to apply the theme to the HTML element.

<html>
	<head />
	<body>
		<Providers>
			<main>{children}</main>
		</Providers>
	</body>
</html>

Create a Providers Component

"use client"
import { ThemeProvider } from "next-themes"
 
const Providers = ({ children }: { children: React.ReactNode }) => {
	return (
		<ThemeProvider enableSystem={true} attribute="class">
			{children}
		</ThemeProvider>
	)
}
 
export default Providers

Create a Dark Mode Switch Component

Now let's create a component to toggle between light mode and dark mode.

Create a new component called DarkModeToggle.tsx in the components directory. Here's an example:

"use client"
import { useState, useEffect } from "react"
import { useTheme } from "next-themes"
import { MoonIcon, SunIcon } from "@heroicons/react/24/solid"
 
const DarkModeBtn = () => {
	const [mounted, setMounted] = useState(false)
	const { systemTheme, theme, setTheme } = useTheme()
 
	useEffect(() => {
		setMounted(true)
	}, [])
 
	if (!mounted) {
		return null
	}
 
	const currentTheme = theme === "system" ? systemTheme : theme
 
	return (
		<div>
			{currentTheme === "dark" ? (
				<SunIcon
					className="h-6 w-6 cursor-pointer text-yellow-400"
					onClick={() => setTheme("light")}
				/>
			) : (
				<MoonIcon
					className="h-6 w-6 cursor-pointer text-slate-700"
					onClick={() => setTheme("dark")}
				/>
			)}
		</div>
	)
}
export default DarkModeBtn

This component is toggled when the user clicks on the button. The state is saved to localStorage so that the user's preference is remembered when they revisit the website.

Add the Dark Mode

<DarkModeBtn />