Introduction to Styling in Next.js | Styling and Components: Building User Interfaces | Next.js: A Practical Introduction for Developers

Welcome to the exciting world of styling your Next.js applications! In this chapter, we'll explore the various ways you can bring your user interfaces to life, from simple CSS to more advanced styling techniques. Next.js offers a flexible and powerful styling ecosystem that empowers you to build beautiful and performant web applications.

Choosing the right styling approach for your project depends on your team's preferences, the complexity of your UI, and your desired level of maintainability. Next.js supports several popular styling methods out-of-the-box or with minimal configuration.

Here's a quick overview of the styling options we'll cover:

Global CSS: Applying styles that affect the entire application.
CSS Modules: Encapsulating styles to prevent conflicts between components.
Styled-JSX: Inline styling with the power of CSS.
Tailwind CSS: A utility-first CSS framework for rapid UI development.
Sass/SCSS: Preprocessor support for more advanced CSS features.

Let's dive into each of these methods to understand how they work within the Next.js framework.

Global CSS is the simplest way to add styles to your Next.js application. You can import a CSS file directly into your pages/_app.js file. This makes the styles available throughout your entire application. For instance, you might use global CSS for resetting default browser styles or for defining global typography and color palettes.

import '../styles/globals.css';

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

While global CSS is convenient, it can lead to style collisions in larger applications where multiple components might accidentally share the same class names. This is where CSS Modules come into play.

CSS Modules are a system where CSS files are scoped locally by default. When you import a CSS Module into a component, Next.js generates unique class names, ensuring that your styles are isolated to that specific component. This significantly reduces the risk of unintended style overrides and makes your component styles more predictable and maintainable.

To use CSS Modules, simply name your CSS files with the .module.css extension (e.g., MyComponent.module.css). You can then import these styles as an object in your JavaScript component.

// components/MyComponent.module.css
.title {
  color: blue;
  font-size: 24px;
}

// components/MyComponent.js
import styles from './MyComponent.module.css';

function MyComponent() {
  return <h1 className={styles.title}>Hello from My Component</h1>;
}

Next.js also offers built-in support for Styled-JSX, a popular library for writing CSS directly within your JavaScript components. This allows you to colocate your styles with your component logic, making it easier to understand and manage the styling for each individual UI element. It also provides automatic style scoping, similar to CSS Modules.

import React from 'react';

const MyStyledComponent = () => (
  <>
    <style jsx>{`
      h1 {
        color: green;
      }
    `}</style>
    <h1>Styled JSX Example</h1>
  </>
);

export default MyStyledComponent;

For developers who prefer a utility-first approach, Tailwind CSS is an excellent choice. Next.js provides seamless integration with Tailwind CSS, allowing you to build complex UIs rapidly by composing small, pre-defined utility classes directly in your HTML markup.

<h1 className="text-4xl font-bold text-blue-600">Tailwind CSS Example</h1>

Lastly, Next.js fully supports Sass and SCSS. You can leverage the power of Sass features like variables, mixins, and nesting to write more organized and maintainable CSS. To use Sass/SCSS, you'll typically need to install the sass package.

npm install sass

// styles/MyComponent.scss
$primary-color: red;

.container {
  color: $primary-color;
  padding: 10px;
}

// components/MyComponent.js
import './MyComponent.scss';

function MyComponent() {
  return <div className="container">Sass Example</div>;
}

Understanding these different styling options will help you choose the best approach for your Next.js project, enabling you to build visually appealing and well-structured user interfaces.

// components/MyComponent.module.css .title { color: blue; font-size: 24px; } // components/MyComponent.js import styles from './MyComponent.module.css'; function MyComponent() { return <h1 className={styles.title}>Hello from My Component</h1>; }

import React from 'react'; const MyStyledComponent = () => ( <> <style jsx>{` h1 { color: green; } `}</style> <h1>Styled JSX Example</h1> </> ); export default MyStyledComponent;

// styles/MyComponent.scss $primary-color: red; .container { color: $primary-color; padding: 10px; } // components/MyComponent.js import './MyComponent.scss'; function MyComponent() { return <div className="container">Sass Example</div>; }