Using CSS-in-JS Libraries in Next.js: Styling with JavaScript

CSS-in-JS libraries are a popular way to style modern web applications, allowing you to write CSS directly in your JavaScript components. In Next.js, you can use CSS-in-JS libraries like styled-components, emotion, or linaria to create dynamic and reusable styles. In this article, we’ll explore how to use CSS-in-JS libraries in Next.js, including setup, usage, and best practices.

What are CSS-in-JS Libraries?

CSS-in-JS libraries allow you to write CSS directly in your JavaScript components, making it easier to manage styles in large and complex applications. These libraries provide features like scoped styles, dynamic styles, and theme support, making them a powerful tool for modern web development.

Using CSS-in-JS Libraries in Next.js

To use a CSS-in-JS library in Next.js, you need to install the library and configure it to work with Next.js. Here’s how to use styled-components as an example:

1. Install the Library

First, install the CSS-in-JS library and its dependencies. For styled-components, run the following command:

npm install styled-components babel-plugin-styled-components

2. Configure Babel

Next, configure Babel to use the CSS-in-JS library. Create a .babelrc file in the root of your project and add the following configuration:

{
  "presets": ["next/babel"],
  "plugins": [["styled-components", { "ssr": true }]]
}

3. Create a Component

Now, you can create a component using the CSS-in-JS library. Here’s an example using styled-components:

// components/Button.js
import styled from 'styled-components';

const Button = styled.button`
  background-color: #0070f3;
  color: white;
  padding: 10px 20px;
  border: none;
  border-radius: 5px;
  cursor: pointer;

  &:hover {
    background-color: #005bb5;
  }
`;

export default Button;

In this example, the Button component is styled using styled-components.

4. Use the Component

Finally, use the styled component in your application. Here’s an example:

// pages/index.js
import Button from '../components/Button';

export default function Home() {
  return (
    <div>
      <h1>Welcome to My Next.js App!</h1>
      <Button>Click me</Button>
    </div>
  );
}

Benefits of CSS-in-JS Libraries

CSS-in-JS libraries offer several benefits:

• Scoped Styles: CSS-in-JS libraries automatically scope styles to the component, preventing style conflicts.
• Dynamic Styles: You can dynamically generate styles using JavaScript, making it easier to create responsive and interactive components.
• Theme Support: CSS-in-JS libraries provide built-in support for themes, allowing you to easily switch between different styles.

Secrets and Hidden Facts

• Server-side Rendering: CSS-in-JS libraries support server-side rendering, ensuring that styles are applied correctly on the server.
• Performance Optimization: Use tools like linaria to generate static CSS files for better performance.
• Custom Hooks: Use custom hooks to manage styles and themes in CSS-in-JS libraries.

Conclusion

CSS-in-JS libraries are a powerful tool for styling modern web applications, allowing you to write CSS directly in your JavaScript components. Whether you’re using styled-components, emotion, or linaria, Next.js provides the tools and flexibility you need to create dynamic and reusable styles.