Next.js provides built-in support for Sass and SCSS, allowing you to use these popular CSS preprocessors in your applications. Sass (Syntactically Awesome Style Sheets) is a powerful stylesheet language that extends CSS with features like variables, nested rules, mixins, and more. SCSS is a syntax of Sass that is fully compatible with CSS and is widely used due to its ease of use.

Key Features of Sass/SCSS Support in Next.js

1. Easy Integration: Next.js makes it simple to include Sass/SCSS in your project without additional configuration.

2. Variables and Nesting: You can use Sass features such as variables, nesting, and mixins to write cleaner and more maintainable styles.

3. Modular Styles: SCSS can be used in conjunction with CSS Modules, providing scoped styles while leveraging the features of Sass.

Setting Up Sass/SCSS in Next.js

To use Sass/SCSS in a Next.js project, follow these steps:

Step 1: Install the Necessary Package

First, you need to install the sass package in your Next.js application. You can do this using npm or yarn:

npm install sass

or

yarn add sass

Step 2: Create SCSS Files

Next, create your SCSS files. You can use the .scss extension for your styles. For example, you might create a file named styles.scss in the styles directory:

/styles
  ├── styles.scss

Example SCSS File

Here’s an example of how you might write styles in SCSS:

/* styles/styles.scss */

$primary-color: #0070f3;
$padding: 20px;

.container {
  padding: $padding;
  border: 1px solid #ccc;

  h1 {
    color: $primary-color;
    font-size: 2em;
  }

  .button {
    background-color: $primary-color;
    color: white;
    border: none;
    padding: 10px 15px;
    cursor: pointer;
    
    &:hover {
      background-color: darken($primary-color, 10%);
    }
  }
}

Step 3: Import the SCSS File

You need to import the SCSS file in your component or the _app.js file to use the styles. If the styles are global, it’s common to import them in _app.js:

// pages/_app.js

import '../styles/styles.scss'; // Import SCSS styles

function MyApp({ Component, pageProps }) {
  return <Component {...pageProps} />;
}

export default MyApp;

Using SCSS with CSS Modules

You can also use SCSS with CSS Modules by naming your file with the .module.scss extension. This allows you to take advantage of both CSS Modules and SCSS features.

Example of Using SCSS with CSS Modules

1. Create a SCSS Module file:

/styles
  ├── styles.module.scss

2. Write your SCSS styles:

/* styles/styles.module.scss */

$primary-color: #0070f3;

.container {
  padding: 20px;
  border: 1px solid #ccc;

  h1 {
    color: $primary-color;
    font-size: 2em;
  }

  .button {
    background-color: $primary-color;
    color: white;
    border: none;
    padding: 10px 15px;
    cursor: pointer;

    &:hover {
      background-color: darken($primary-color, 10%);
    }
  }
}

3. Import and use in a component:

// components/MyComponent.js

import styles from '../styles/styles.module.scss';

const MyComponent = () => {
  return (
    <div className={styles.container}>
      <h1>Hello, SCSS Modules!</h1>
      <button className={styles.button}>Click Me</button>
    </div>
  );
};

export default MyComponent;

Advantages of Using Sass/SCSS

1. Enhanced Syntax: Sass/SCSS provides features like variables, nesting, and mixins, making your stylesheets more maintainable and easier to read.

2. Modular and Scoped Styles: When combined with CSS Modules, SCSS helps keep styles scoped to individual components, reducing the risk of style conflicts.

3. Built-in Support: Next.js’s built-in support for Sass means you don’t have to configure build tools manually, simplifying the setup process.

Important Considerations

• File Naming: Use the .scss extension for standard SCSS files and .module.scss for CSS Modules.

• Mixing Styles: You can mix global SCSS files with CSS Modules, but ensure you understand how scope works in CSS Modules to avoid unexpected style conflicts.

• Performance: While Sass can enhance development, it’s essential to keep an eye on the output CSS size to maintain good performance in your application.

Summary

Sass/SCSS support in Next.js allows developers to leverage the powerful features of Sass while benefiting from the framework’s built-in optimizations. By using SCSS, you can write more modular, maintainable, and organized styles, enhancing your Next.js applications’ overall quality and performance. Whether you’re creating simple styles or complex design systems, Sass/SCSS provides the flexibility needed to build beautiful user interfaces.