---
title: How to use Sass
nav_title: Sass
description: Style your Next.js application using Sass.
---
{/* The content of this doc is shared between the app and pages router. You can use the `Content` component to add content that is specific to the Pages Router. Any shared content should not be wrapped in a component. */}
Next.js has built-in support for integrating with Sass after the package is installed using both the `.scss` and `.sass` extensions. You can use component-level Sass via CSS Modules and the `.module.scss`or `.module.sass` extension.
First, install [`sass`](https://github.com/sass/sass):
```bash filename="Terminal"
npm install --save-dev sass
```
> **Good to know**:
>
> Sass supports [two different syntaxes](https://sass-lang.com/documentation/syntax), each with their own extension.
> The `.scss` extension requires you use the [SCSS syntax](https://sass-lang.com/documentation/syntax#scss),
> while the `.sass` extension requires you use the [Indented Syntax ("Sass")](https://sass-lang.com/documentation/syntax#the-indented-syntax).
>
> If you're not sure which to choose, start with the `.scss` extension which is a superset of CSS, and doesn't require you learn the
> Indented Syntax ("Sass").
### Customizing Sass Options
If you want to configure your Sass options, use `sassOptions` in `next.config`.
```ts filename="next.config.ts" switcher
import type { NextConfig } from 'next'
const nextConfig: NextConfig = {
sassOptions: {
additionalData: `$var: red;`,
},
}
export default nextConfig
```
```js filename="next.config.js" switcher
/** @type {import('next').NextConfig} */
const nextConfig = {
sassOptions: {
additionalData: `$var: red;`,
},
}
module.exports = nextConfig
```
#### Implementation
You can use the `implementation` property to specify the Sass implementation to use. By default, Next.js uses the [`sass`](https://www.npmjs.com/package/sass) package.
```ts filename="next.config.ts" switcher
import type { NextConfig } from 'next'
const nextConfig: NextConfig = {
sassOptions: {
implementation: 'sass-embedded',
},
}
export default nextConfig
```
```js filename="next.config.js" switcher
/** @type {import('next').NextConfig} */
const nextConfig = {
sassOptions: {
implementation: 'sass-embedded',
},
}
module.exports = nextConfig
```
### Sass Variables
Next.js supports Sass variables exported from CSS Module files.
For example, using the exported `primaryColor` Sass variable:
```scss filename="app/variables.module.scss"
$primary-color: #64ff00;
:export {
primaryColor: $primary-color;
}
```
```jsx filename="app/page.js"
// maps to root `/` URL
import variables from './variables.module.scss'
export default function Page() {
return Hello, Next.js!
}
```
```jsx filename="pages/_app.js"
import variables from '../styles/variables.module.scss'
export default function MyApp({ Component, pageProps }) {
return (
)
}
```