How to Style React Components: CSS, Styled Components & More

Learn how to style React components with CSS, CSS Modules, Styled Components, Emotion, and Tailwind CSS for scalable, maintainable UIs.

React has become one of the most popular libraries for building modern web applications. As developers, we’re tasked with building aesthetically pleasing user interfaces that are not only functional but also maintainable and scalable. Styling React components is a crucial part of this process. Fortunately, there are several ways to style React components, and understanding the various approaches can help you decide which one fits best with your development workflow.

1. The Basics of Styling React Components

1.1 Why React Components Need Styling

In React, the components are the fundamental building blocks of your application. Each component represents a part of the UI, and styling them is essential for creating an engaging, user-friendly interface. Whether you’re building a simple UI or a complex application, styling determines the look and feel of the final product.

React’s component-based architecture means that each component can have its own styles. However, the challenge lies in managing styles effectively and ensuring they are scoped correctly to avoid conflicts. Below, we’ll explore several methods to solve this challenge.

2. Traditional CSS for React Components

2.1 Using Plain CSS in React

Using plain CSS is the most traditional approach to styling React components. In this method, you create separate .css files and link them to your components. These styles are global, meaning they affect the entire application unless scoped correctly.

Example:

/* styles.css */
.button {
  background-color: blue;
  color: white;
  padding: 10px 20px;
}

// Button.jsx
import React from 'react';
import './styles.css';

const Button = () => {
  return <button className="button">Click Me</button>;
};

export default Button;

Pros:

• Easy to implement.
• Well understood by most developers, as CSS is universally used.
• Works seamlessly for simple applications with few components.

Cons:

• Global styles can cause conflicts, especially in larger applications.
• No automatic scoping of styles to specific components.
• Can lead to “CSS leakage” where styles from one component affect others.

2.2 Best Practices with Plain CSS

To avoid conflicts, it’s recommended to:

• Use a naming convention like BEM (Block, Element, Modifier) to reduce the risk of global style conflicts.
• Organize your CSS by feature or component to make it easier to maintain.

3. CSS Modules: Scoped Styling in React

3.1 What Are CSS Modules?

CSS Modules are an excellent solution for scoping styles to individual components. In a CSS Module, each class name is scoped locally by default. This means that the class names in a CSS Module are unique to the component, preventing global conflicts.

When using CSS Modules, React automatically generates unique class names for each component’s styles, which prevents the problem of global styles leaking across components.

Example:

/* Button.module.css */
.button {
  background-color: green;
  color: white;
  padding: 10px 20px;
}

// Button.jsx
import React from 'react';
import styles from './Button.module.css';

const Button = () => {
  return <button className={styles.button}>Click Me</button>;
};

export default Button;

Pros:

• Styles are scoped to the component, preventing global conflicts.
• Works well with large applications where CSS organization is crucial.
• Easier to maintain as styles are encapsulated within their respective components.

Cons:

• Slightly more complex than plain CSS.
• Requires a build setup that supports CSS Modules (e.g., Webpack).

4. Styled Components: CSS-in-JS

4.1 What is Styled Components?

Styled Components is a library that allows you to write CSS directly inside your JavaScript files using tagged template literals. This approach is known as CSS-in-JS, and it has gained a lot of popularity in the React community because it allows you to scope your styles to components while keeping everything in a single file.

With Styled Components, styles are bound to the components themselves, ensuring that no other component can accidentally override or access them. This approach also provides support for dynamic styling based on component props.

Example:

import React from 'react';
import styled from 'styled-components';

const Button = styled.button`
  background-color: ${(props) => (props.primary ? 'blue' : 'gray')};
  color: white;
  padding: 10px 20px;
`;

const App = () => {
  return <Button primary>Click Me</Button>;
};

export default App;

Pros:

• Styles are scoped and encapsulated within the component.
• Supports dynamic styling based on component props.
• No need for external CSS files, making everything self-contained.
• Supports theming and other advanced CSS features.

Cons:

• Can make the JavaScript files larger, especially with many styled components.
• Can be difficult to manage if not organized properly, especially for large apps.

4.2 When to Use Styled Components

Styled Components are ideal for projects where:

• You want to keep styles scoped to components.
• You prefer the flexibility of CSS-in-JS for dynamic styling.
• You need support for theming and global styles within the JavaScript ecosystem.

5. Emotion: Another CSS-in-JS Library

5.1 What is Emotion?

Emotion is another popular CSS-in-JS library that provides powerful tools for styling React components. It offers two main methods for styling: styled components (like in the Styled Components library) and the css prop, which lets you apply styles directly within your JSX.

Example:

/** @jsxImportSource @emotion/react */
import { css } from '@emotion/react';

const buttonStyle = css`
  background-color: red;
  color: white;
  padding: 10px 20px;
`;

const Button = () => {
  return <button css={buttonStyle}>Click Me</button>;
};

export default Button;

Pros:

• Extremely flexible and allows you to use styles in various ways.
• Supports theming, global styles, and server-side rendering (SSR).
• Lightweight and fast.

Cons:

• Can lead to large JavaScript bundles if not managed correctly.
• May require some learning curve if you’re not familiar with CSS-in-JS.

5.2 Emotion vs. Styled Components

Both Emotion and Styled Components provide similar functionality, but Emotion is often considered more lightweight and faster. It also has a slightly more flexible API, which can be beneficial for developers looking for more control over their styles.

6. Tailwind CSS: Utility-First Styling

6.1 What is Tailwind CSS?

Tailwind CSS is a utility-first CSS framework that allows you to build custom designs by composing utility classes directly in your JSX. Rather than writing traditional CSS, you apply pre-built classes to elements in your components.

Example:

const Button = () => {
  return <button className="bg-blue-500 text-white p-2 rounded">Click Me</button>;
};

export default Button;

Pros:

• Highly customizable, allowing you to design complex UIs without writing custom CSS.
• Encourages consistency and reusability with utility classes.
• Keeps your JSX files clean and readable without relying on separate CSS files.

Cons:

• Can lead to cluttered JSX files with many utility classes.
• May require a learning curve if you’re not familiar with the utility-first approach.

6.2 When to Use Tailwind CSS

Tailwind CSS is best suited for developers who prefer utility-first CSS and want to avoid writing custom CSS. It’s great for building responsive, customizable designs quickly, without needing to manage large CSS files or worry about class name conflicts.

7. Conclusion: Choosing the Right Styling Approach

Styling React components can be done in several ways, each with its own pros and cons. The method you choose will depend on your project’s requirements and your team’s workflow. Here’s a quick summary:

• Plain CSS is great for small applications or when you want simple, global styles.
• CSS Modules are ideal for medium-sized applications where styles should be scoped to individual components.
• Styled Components and Emotion provide CSS-in-JS solutions that allow for scoped, dynamic styling.
• Tailwind CSS is perfect for developers who prefer utility-first CSS and want to build responsive UIs quickly.

Ultimately, the best choice will depend on the scale of your application, your team’s preferences, and the complexity of your styling needs.