Introduction
CSS-in-JS is a popular approach for styling React applications, allowing you to write CSS directly within JavaScript files. This method offers several advantages, including scoped styles, dynamic theming, and easier maintenance. This cheatsheet covers some of the most widely-used CSS-in-JS libraries, providing a brief overview of each and examples of how they can be used in your React projects.
1. Styled Components
Styled Components is one of the most popular CSS-in-JS libraries, enabling developers to create styled React components with ease.
| Feature | Description | Example |
|---|
| Tagged Template Literals | Uses tagged template literals to style your components. | const Button = styled.button\background: palevioletred; color: white;\; |
| Theming | Easily create and use themes across your application. | <ThemeProvider theme={theme}></ThemeProvider> |
| Dynamic Styling | Styles can be dynamically changed based on props or state. | color: \${props => props.primary ? "white" : "palevioletred"}; |
Pros:
- Familiar CSS syntax with additional JS power.
- Strong community and ecosystem support.
- Supports server-side rendering and theming.
Cons:
- Can introduce overhead with large stylesheets.
- May require Babel configuration for optimal usage.
2. Emotion
Emotion is a performant and flexible CSS-in-JS library that provides both styled and traditional CSS approaches.
| Feature | Description | Example |
|---|
| CSS-in-JS | Write styles with JavaScript using the css function. | const style = css\color: hotpink;\; |
| Styled Components | Create styled components with @emotion/styled. | const Button = styled.button\background: hotpink;\; |
| Server-Side Rendering | Built-in SSR support without additional configuration. | <Global styles={css\body { margin: 0; }\} /> |
Pros:
- Very fast and lightweight.
- Flexible API that supports multiple styling methods.
- Excellent TypeScript support.
Cons:
- Slightly steeper learning curve due to flexibility.
- Somewhat smaller community compared to Styled Components.
3. JSS (JavaScript Style Sheets)
JSS is an authoring tool that allows you to use JavaScript to describe styles programmatically.
| Feature | Description | Example |
|---|
| Dynamic Styles | Create dynamic styles that can change based on props or state. | const styles = { button: { color: props => props.color } }; |
| Scoped Styles | All styles are scoped to the component. | const { classes } = useStyles(props); |
| Theming | Built-in theming capabilities. | <ThemeProvider theme={theme}></ThemeProvider> |
Pros:
- Very flexible and powerful for complex apps.
- Works well with other styling solutions.
- Integrated into Material-UI.
Cons:
- More verbose syntax.
- Smaller ecosystem and community support.
4. Linaria
Linaria is a zero-runtime CSS-in-JS library that generates real CSS files at build time.
| Feature | Description | Example |
|---|
| Zero Runtime | Generates CSS files at build time, no runtime overhead. | const title = css\font-size: 24px;\; |
| CSS Variables | Supports dynamic CSS variables for theming. | color: var(--main-color); |
| Styled Components | Styled-components syntax with zero-runtime cost. | const Button = styled.button\padding: 8px 16px;\; |
Pros:
- Zero runtime cost.
- Uses native CSS syntax.
- Great for performance-critical apps.
Cons:
- Limited support for advanced dynamic styling.
- Smaller community.
5. Stitches
Stitches is a CSS-in-JS library focused on fast styling with a utility-first API.
| Feature | Description | Example |
|---|
| Utility-First | Provides utilities similar to Tailwind. | const Button = styled('button', { backgroundColor: 'blue' }); |
| Atomic CSS | Generates atomic CSS classes. | .bg-blue { background-color: blue; } |
| Variants | Allows creation of component variants easily. | const Button = styled('button', { variants: { size: { small: { fontSize: '12px' } } } }); |
Pros:
- Very fast with minimal runtime overhead.
- Small bundle size and optimized CSS output.
- Easy integration with existing styling approaches.
Cons:
- Limited community and resources.
- Relatively new, so less adoption.
Conclusion
CSS-in-JS libraries provide a powerful way to manage styles in React applications, offering scoped styles, dynamic theming, and improved maintainability. Whether building a small project or a large-scale application, these tools can help you manage your styles effectively.
📌 Consider your project's complexity, performance needs, and team preference when choosing a CSS-in-JS solution.