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---
title: CSS
description: Learn about the different ways to add CSS to your application, including CSS Modules, Global CSS, Tailwind CSS, and more.
related:
title: Next Steps
description: Learn more about the alternatives ways you can use CSS in your application.
links:
- app/guides/tailwind-css
- app/guides/sass
- app/guides/css-in-js
---
Next.js provides several ways to style your application using CSS, including:
- [CSS Modules](#css-modules)
- [Global CSS](#global-css)
- [External Stylesheets](#external-stylesheets)
- [Tailwind CSS](/docs/app/guides/tailwind-css)
- [Sass](/docs/app/guides/sass)
- [CSS-in-JS](/docs/app/guides/css-in-js)
## CSS Modules
CSS Modules locally scope CSS by generating unique class names. This allows you to use the same class in different files without worrying about naming collisions.
<AppOnly>
To start using CSS Modules, create a new file with the extension `.module.css` and import it into any component inside the `app` directory:
```css filename="app/blog/blog.module.css"
.blog {
padding: 24px;
}
```
```tsx filename="app/blog/page.tsx" switcher
import styles from './blog.module.css'
export default function Page() {
return <main className={styles.blog}></main>
}
```
```jsx filename="app/blog/page.js" switcher
import styles from './blog.module.css'
export default function Layout() {
return <main className={styles.blog}></main>
}
```
</AppOnly>
<PagesOnly>
To start using CSS Modules, create a new file with the extension `.module.css` and import it into any component inside the `pages` directory:
```css filename="/styles/blog.module.css"
.blog {
padding: 24px;
}
```
```tsx filename="pages/blog/index.tsx" switcher
import styles from './blog.module.css'
export default function Page() {
return <main className={styles.blog}></main>
}
```
```jsx filename="pages/blog/index.js" switcher
import styles from './blog.module.css'
export default function Page() {
return <main className={styles.blog}></main>
}
```
</PagesOnly>
## Global CSS
You can use global CSS to apply styles across your application.
<AppOnly>
Create a `app/global.css` file and import it in the root layout to apply the styles to **every route** in your application:
```css filename="app/global.css"
body {
padding: 20px 20px 60px;
max-width: 680px;
margin: 0 auto;
}
```
```tsx filename="app/layout.tsx" switcher
// These styles apply to every route in the application
import './global.css'
export default function RootLayout({
children,
}: {
children: React.ReactNode
}) {
return (
<html lang="en">
<body>{children}</body>
</html>
)
}
```
```jsx filename="app/layout.js" switcher
// These styles apply to every route in the application
import './global.css'
export default function RootLayout({ children }) {
return (
<html lang="en">
<body>{children}</body>
</html>
)
}
```
> **Good to know:** Global styles can be imported into any layout, page, or component inside the `app` directory. However, since Next.js uses React's built-in support for stylesheets to integrate with Suspense, this currently does not remove stylesheets as you navigate between routes which can lead to conflicts. We recommend using global styles for _truly_ global CSS, and [CSS Modules](#css-modules) for scoped CSS.
</AppOnly>
<PagesOnly>
Import the stylesheet in the `pages/_app.js` file to apply the styles to **every route** in your application:
```tsx filename="pages/_app.js"
import '@/styles/global.css'
export default function MyApp({ Component, pageProps }) {
return <Component {...pageProps} />
}
```
Due to the global nature of stylesheets, and to avoid conflicts, you should import them inside [`pages/_app.js`](/docs/pages/building-your-application/routing/custom-app).
</PagesOnly>
## External stylesheets
<AppOnly>
Stylesheets published by external packages can be imported anywhere in the `app` directory, including colocated components:
```tsx filename="app/layout.tsx" switcher
import 'bootstrap/dist/css/bootstrap.css'
export default function RootLayout({
children,
}: {
children: React.ReactNode
}) {
return (
<html lang="en">
<body className="container">{children}</body>
</html>
)
}
```
```jsx filename="app/layout.js" switcher
import 'bootstrap/dist/css/bootstrap.css'
export default function RootLayout({ children }) {
return (
<html lang="en">
<body className="container">{children}</body>
</html>
)
}
```
> **Good to know:** In React 19, `<link rel="stylesheet" href="..." />` can also be used. See the [React `link` documentation](https://react.dev/reference/react-dom/components/link) for more information.
</AppOnly>
<PagesOnly>
Next.js allows you to import CSS files from a JavaScript file. This is possible because Next.js extends the concept of [`import`](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/import) beyond JavaScript.
### Import styles from `node_modules`
Since Next.js **9.5.4**, importing a CSS file from `node_modules` is permitted anywhere in your application.
For global stylesheets, like `bootstrap` or `nprogress`, you should import the file inside `pages/_app.js`. For example:
```jsx filename="pages/_app.js"
import 'bootstrap/dist/css/bootstrap.css'
export default function MyApp({ Component, pageProps }) {
return <Component {...pageProps} />
}
```
To import CSS required by a third-party component, you can do so in your component. For example:
```jsx filename="components/example-dialog.js"
import { useState } from 'react'
import { Dialog } from '@reach/dialog'
import VisuallyHidden from '@reach/visually-hidden'
import '@reach/dialog/styles.css'
function ExampleDialog(props) {
const [showDialog, setShowDialog] = useState(false)
const open = () => setShowDialog(true)
const close = () => setShowDialog(false)
return (
<div>
<button onClick={open}>Open Dialog</button>
<Dialog isOpen={showDialog} onDismiss={close}>
<button className="close-button" onClick={close}>
<VisuallyHidden>Close</VisuallyHidden>
<span aria-hidden>×</span>
</button>
<p>Hello there. I am a dialog</p>
</Dialog>
</div>
)
}
```
</PagesOnly>
## Ordering and Merging
Next.js optimizes CSS during production builds by automatically chunking (merging) stylesheets. The **order of your CSS** depends on the **order you import styles in your code**.
For example, `base-button.module.css` will be ordered before `page.module.css` since `<BaseButton>` is imported before `page.module.css`:
```tsx filename="page.tsx" switcher
import { BaseButton } from './base-button'
import styles from './page.module.css'
export default function Page() {
return <BaseButton className={styles.primary} />
}
```
```jsx filename="page.js" switcher
import { BaseButton } from './base-button'
import styles from './page.module.css'
export default function Page() {
return <BaseButton className={styles.primary} />
}
```
```tsx filename="base-button.tsx" switcher
import styles from './base-button.module.css'
export function BaseButton() {
return <button className={styles.primary} />
}
```
```jsx filename="base-button.js" switcher
import styles from './base-button.module.css'
export function BaseButton() {
return <button className={styles.primary} />
}
```
### Recommendations
To keep CSS ordering predictable:
- Try to contain CSS imports to a single JavaScript or TypeScript entry file
- Import global styles and Tailwind stylesheets in the root of your application.
- Use CSS Modules instead of global styles for nested components.
- Use a consistent naming convention for your CSS modules. For example, using `<name>.module.css` over `<name>.tsx`.
- Extract shared styles into shared components to avoid duplicate imports.
- Turn off linters or formatters that auto-sort imports like ESLint’s [`sort-imports`](https://eslint.org/docs/latest/rules/sort-imports).
- You can use the [`cssChunking`](/docs/app/api-reference/config/next-config-js/cssChunking) option in `next.config.js` to control how CSS is chunked.
## Development vs Production
- In development (`next dev`), CSS updates apply instantly with [Fast Refresh](/docs/architecture/fast-refresh).
- In production (`next build`), all CSS files are automatically concatenated into **many minified and code-split** `.css` files, ensuring the minimal amount of CSS is loaded for a route.
- CSS still loads with JavaScript disabled in production, but JavaScript is required in development for Fast Refresh.
- CSS ordering can behave differently in development, always ensure to check the build (`next build`) to verify the final CSS order.
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