@mayank1513/nextjs-themes-lite NPM

Nextjs-Themes

We are launching version 3.0 with minor API changes and major performance improvement and fixes. We have tried our best to ensure minimum changes to existing APIs. For most users we recommend using nthul package.
We recommend using react18-themes for Remix. This package is maintained with specific focus on Next.js and Vite. Most of the functionality of this package along with extended support for other build tools is available in react18-themes

🤟 👉 Unleash the Power of React Server Components

This project was originally inspired by next-themes. Next-themes is an awesome package, however, it requires wrapping everything in a provider. The provider has to be a client component as it uses hooks. And thus, it takes away all the benefits of Server Components.

@mayank1513/nextjs-themes-lite removes this limitation and enables you to unleash the full power of React 18 Server Components. In addition, it adds more features and control over how you theme your app. Stay tuned!

✅ Perfect dark mode in 2 lines of code
✅ Fully Treeshakable (import from @mayank1513/nextjs-themes-lite/client/component)
✅ Designed for excellence
✅ Full TypeScript Support
✅ Unleash the full power of React18 Server components
✅ Perfect dark mode in 2 lines of code
✅ System setting with prefers-color-scheme
✅ Themed browser UI with color-scheme
✅ Support for Next.js 13 & Next.js 14 appDir
✅ No flash on load (for all - SSG, SSR, ISG, Server Components)
✅ Sync theme across tabs and windows
✅ Disable flashing when changing themes
✅ Force pages to specific themes
✅ Class and data attribute selector
✅ Manipulate theme via useTheme hook
✅ Documented with Typedoc (Docs)
✅ Use combinations of data-th="" and data-color-scheme="" for dark/light varients of themes
✅ Use data-csp="" to style based on colorSchemePreference.
✅ Want to avoid cookies (Not recommended), set storage prop to localStorage or sessionStorage (to avoid persistance)

Check out the live example.

Install

$ pnpm add @mayank1513/nextjs-themes-lite

$ npm install @mayank1513/nextjs-themes-lite

$ yarn add @mayank1513/nextjs-themes-lite

To do

Update examples, docs and Readme

Usage

SPA (e.g., Vite, CRA) and Next.js pages directory (No server components)

The best way is to add a Custom App to use by modifying _app as follows:

Adding dark mode support takes 2 lines of code:

import { ThemeSwitcher } from "@mayank1513/nextjs-themes-lite";

function MyApp({ Component, pageProps }) {
  return (
    <>
      <ThemeSwitcher forcedTheme={Component.theme} />
      <Component {...pageProps} />
    </>
  );
}

export default MyApp;

⚡🎉Boom! Just a couple of lines and your dark mode is ready!

Check out examples for advanced usage.

With Next.js `app` router (Server Components)

Prefer static generation over SSR - No wrapper component

If your app is mostly serving static content, you do not want the overhead of SSR. Use NextJsSSGThemeSwitcher in this case. When using this approach, you need to use CSS general sibling Combinator (~) to make sure your themed CSS is properly applied. See (HTML & CSS)#html--css.

Update your app/layout.jsx to add ThemeSwitcher from @mayank1513/nextjs-themes-lite, and NextJsSSGThemeSwitcher from @mayank1513/nextjs-themes-lite/server. NextJsSSGThemeSwitcher is required to avoid flash of un-themed content on reload.

// app/layout.jsx
import { ThemeSwitcher } from "@mayank1513/nextjs-themes-lite";
import { NextJsSSGThemeSwitcher } from "@mayank1513/nextjs-themes-lite/server/nextjs";

export default function Layout({ children }) {
  return (
    <html lang="en">
      <head />
      <body>
        /** use NextJsSSGThemeSwitcher as first element inside body */
        <NextJsSSGThemeSwitcher />
        <ThemeSwitcher />
        {children}
      </body>
    </html>
  );
}

Woohoo! You just added multiple theme modes and you can also use Server Component! Isn't that awesome!

Prefer SSR over SSG - Use wrapper component

If your app is serving dynamic content and you want to utilize SSR, continue using ServerSideWrapper component to replace html tag in layout.tsx file.

Update your app/layout.jsx to add ThemeSwitcher and ServerSideWrapper from @mayank1513/nextjs-themes-lite. ServerSideWrapper is required to avoid flash of un-themed content on reload.

// app/layout.jsx
import { ThemeSwitcher } from "@mayank1513/nextjs-themes-lite";
import { ServerSideWrapper } from "@mayank1513/nextjs-themes-lite/server/nextjs";

export default function Layout({ children }) {
  return (
    <ServerSideWrapper tag="html" lang="en">
      <head />
      <body>
        <ThemeSwitcher />
        {children}
      </body>
    </ServerSideWrapper>
  );
}

Woohoo! You just added dark mode and you can also use Server Component! Isn't that awesome!

HTML & CSS

That's it, your Next.js app fully supports dark mode, including System preference with prefers-color-scheme. The theme is also immediately synced between tabs. By default, @mayank1513/nextjs-themes-lite modifies the data-theme attribute on the html element, which you can easily use to style your app:

:root {
  /* Your default theme */
  --background: white;
  --foreground: black;
}

[data-theme="dark"] {
  --background: black;
  --foreground: white;
}

// v2 onwards when using NextJsSSGThemeSwitcher, we need to use CSS Combinators
[data-theme="dark"] ~ * {
  --background: black;
  --foreground: white;
}

Images

You can also show different images based on the current theme.

import Image from "next/image";
import { useTheme } from "@mayank1513/nextjs-themes-lite";

function ThemedImage() {
  const { resolvedTheme } = useTheme();
  let src;

  switch (resolvedTheme) {
    case "light":
      src = "/light.png";
      break;
    case "dark":
      src = "/dark.png";
      break;
    default:
      src = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7";
      break;
  }

  return <Image src={src} width={400} height={400} />;
}

export default ThemedImage;

useTheme

In case your components need to know the current theme and be able to change it. The useTheme hook provides theme information:

import { useTheme } from "@mayank1513/nextjs-themes-lite";

const ThemeChanger = () => {
  const { theme, setTheme } = useTheme();

  return (
    <div>
      The current theme is: {theme}
      <button onClick={() => setTheme("light")}>Light Mode</button>
      <button onClick={() => setTheme("dark")}>Dark Mode</button>
    </div>
  );
};

Force per page theme and color-scheme

Next.js app router

import { ForceTheme } from "@mayank1513/nextjs-themes-lite";

function MyPage() {
  return (
    <>
      <ForceTheme theme={"my-theme"} />
      ...
    </>
  );
}

export default MyPage;

Next.js pages router

For pages router, you have 2 options. One is the same as the app router and the other option which is compatible with next-themes is to add theme to your page component as follows.

function MyPage() {
  return <>...</>;
}

MyPage.theme = "my-theme";

export default MyPage;

In a similar way, you can also force color scheme.

Forcing color scheme will apply your defaultDark or defaultLight theme, configurable via hooks.

With Styled Components and any CSS-in-JS

Next Themes is completely CSS independent, it will work with any library. For example, with Styled Components you just need to createGlobalStyle in your custom App:

// pages/_app.js
import { createGlobalStyle } from "styled-components";
import { ThemeSwitcher } from "@mayank1513/nextjs-themes-lite";

// Your themeing variables
const GlobalStyle = createGlobalStyle`
  :root {
    --fg: #000;
    --bg: #fff;
  }

  [data-theme="dark"] {
    --fg: #fff;
    --bg: #000;
  }
`;

function MyApp({ Component, pageProps }) {
  return (
    <>
      <GlobalStyle />
      <ThemeSwitcher forcedTheme={Component.theme} />
      <Component {...pageProps} />
    </>
  );
}

With Tailwind

In your tailwind.config.js, set the dark mode property to class:

// tailwind.config.js
module.exports = {
  darkMode: "class",
};

⚡🎉Boom! You are ready to use darkTheme in tailwind.

Caution! Your class must be set to "dark", which is the default value we have used for this library. Tailwind, as of now, requires that class name must be "dark" for dark-theme.

That's it! Now you can use dark-mode specific classes:

<h1 className="text-black dark:text-white">

Migrating from v1 to v2

2.0.0

Major Changes

6f17cce: # Additonal CSS Combinations + Ensure seamless support for Tailwind
- No changes required for client side code as [data-theme=] selectors work as before.
- If you are using ServerSideWrapper or NextJsServerTarget or NextJsSSGThemeSwitcher, you need to convert forcedPages elements to objects of the shape { pathMatcher: RegExp | string; props: ThemeSwitcherProps }.
- Use resolvedColorScheme for more sturdy dark/light/system modes
- Use combinations of [data-th=""] and [data-color-scheme=""] for dark/light varients of themes
- Use [data-csp=""] to style based on colorSchemePreference.

Minor Changes

Support custom themeTransition
- Provide themeTransition prop to ThemeSwitcher component to apply smooth transition while changing theme.
- Use setThemeSet to set lightTheme and darkTheme together.

Motivation:

For server side syncing, we need to use cookies and headers. This means that this component and its children can not be static. They will be rendered server side for each request. Thus, we are avoiding the wrapper. Now, only the NextJsSSGThemeSwitcher will be rendered server side for each request and rest of your app can be server statically.

Take care of the following while migrating to v2.

No changes required for projects not using Next.js app router or server components other than updating cookies policy if needed.
The persistent storage is realized with cookies in place of localStorage. (You might want to update cookies policy accordingly.)
We have provided NextJsSSGThemeSwitcher in addition to ServerSideWrapper for Next.js. You no longer need to use a wrapper component which broke static generation and forced SSR.
Visit With Next.js app router (Server Components)

Migrating from v0 to v1

defaultDarkTheme is renamed to darkTheme
setDefaultDarkTheme is renamed to setDarkTheme
defaultLightTheme is renamed to lightTheme
setDefaultLightTheme is renamed to setLightTheme

Docs

Typedoc

🤩 Don't forger to start this repo!

Want handson course for getting started with Turborepo? Check out React and Next.js with TypeScript

FAQ

Do I need to use CSS variables with this library?

Nope. It's just a convenient way. You can hard code values for every class as follows.

.my-class {
  color: #555;
}

[data-theme="dark"] .my-class {
  color: white;
}

Why is resolvedTheme and resolvedColorScheme necessary?

When supporting the System theme preference, and forced theme/colorScheme pages, you want to make sure that's reflected in your UI. This means your buttons, selects, dropdowns, or whatever you use to indicate the current colorScheme should say "system" when the System colorScheme preference is active. And also the appropreate theme is available in resolvedTheme.

resolvedTheme is then useful for modifying behavior or styles at runtime:

const { resolvedTheme, resolvedColorScheme } = useTheme();

const background = getBackground(resolvedTheme);

<div style={{ color: resolvedColorScheme === 'dark' ? white : black, background }}>

If we didn't have resolvedTheme and only used theme, you'd lose information about the state of your UI (you would only know the theme is "system", and not what it resolved to).