CSS-in-JS is a styling technique where CSS is composed using JavaScript instead of defined in external files. Before we delve into the specifics of various libraries, let's understand why we might need CSS-in-JS.
CSS-in-JS emerged as a solution to several CSS limitations. It allows for dynamic styling, scoped styles, and component-specific styles, which are particularly useful in component-based architectures like React. It also enables the sharing of state between JavaScript and CSS, allowing styles to react to the state changes in your application.
There are several CSS-in-JS libraries available, each with its own strengths and weaknesses. Here, we'll focus on four popular ones: styled-components, emotion, radium, and aphrodite.
Styled-components is one of the most popular CSS-in-JS libraries. It allows you to write actual CSS in your JavaScript, keeping the styling tied to the components. This library also supports server-side rendering, making it a good choice for universal apps.
Emotion is a high-performance library that offers a similar API to styled-components but with a smaller footprint. It supports both the object and string style syntax, and it also allows for the extraction of styles to a separate stylesheet at build time, which can improve load times.
Radium is a set of tools for managing inline styles on React elements. It gives you powerful styling capabilities without CSS. It's especially useful when you want to use features that aren't part of CSS, like media queries or hover.
Aphrodite is another CSS-in-JS library that aims to combine the benefits of inline styles with those of CSS. It automatically concatenates and minifies your styles, and it also supports server-side rendering.
When choosing a CSS-in-JS library, consider the size of the library, the syntax it uses, whether it supports server-side rendering, and how it handles dynamic styles and themes. Each library has its own strengths, so the best one for your project depends on your specific needs and preferences.
In conclusion, CSS-in-JS libraries offer a powerful way to style your JavaScript applications. They provide solutions to many of the limitations of CSS, making it easier to create dynamic, component-specific styles. In the next unit, we'll take a closer look at styled-components, one of the most popular CSS-in-JS libraries.