React18-themes-lite NPM

React 18 Themes

npm bundle size

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.

🤟 👉 Unleash the Power of React Server Components

This project is inspired by next-themes. next-themes is an awesome package, however, it requires wrapping everything in a client side provider. And thus, it takes away all the benefits of Server Components.

react18-themes-lite removes this limitation and enables you to unleash the full power of React 18 Server Components. In addition, more features are coming up soon... Stay tuned!

✅ Fully Treeshakable (import from react18-themes-lite/client/component)
✅ Full TypeScript Support
✅ Unleash the full power of React18 Server components
✅ Works with all build systems/tools/frameworks for React18
✅ 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
✅ Sync theme across tabs and windows
✅ Theme in sync with server component
✅ Disable flashing when changing themes
✅ Force pages to specific themes
✅ Class or data attribute selector
✅ Manipulate theme via useTheme hook
✅ Doccumented 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.
✅ Starting from version 2.3, localStorage is used as default storage. No cookies by default. Use storage="cookies" for smooth initial rendering of server components.

Check out the live example.

Install

$ pnpm add react18-themes-lite

$ npm install react18-themes-lite

$ yarn add react18-themes-lite

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 "react18-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 react18-themes-lite, and NextJsSSGThemeSwitcher from react18-themes-lite/server. NextJsSSGThemeSwitcher is required to avoid flash of un-themed content on reload.

// app/layout.jsx
import { ThemeSwitcher } from "react18-themes-lite";
import { NextJsSSGThemeSwitcher } from "react18-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 react18-themes-lite. ServerSideWrapper is required to avoid flash of un-themed content on reload.

// app/layout.jsx
import { ThemeSwitcher } from "react18-themes-lite";
import { ServerSideWrapper } from "react18-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, react18-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;
}

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 "react18-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 "react18-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.

Changelog

Find changelog here CHANGELOG.md

Migrating from v1 to v2

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.)~~
Starting from version 2.3, persistent storage is again set to localStorage. You can change it to cookies or sassionStorage by passing storage prop to <ThemeSwitcher /> component.
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)