@emotion/core

What is @emotion/core?

The @emotion/core package is a powerful library for writing css styles with JavaScript. It is part of the Emotion library, which is designed to write CSS styles in JavaScript files, allowing for dynamic styling in React applications. It provides APIs to write styles in a more expressive and concise way, supports server-side rendering, and offers a way to compose and reuse styles.

What are @emotion/core's main functionalities?

Styled Components

Allows the creation of styled components using the `css` prop. This feature enables the application of styles directly to components in a React application.

{"import { css } from '@emotion/core';\n\nconst style = css`\n  color: hotpink;\n`;\n\nconst MyComponent = () => (\n  <div css={style}>\n    This is a pink text.\n  </div>\n);"}

Composition

Supports composing multiple style definitions into a single component, allowing for more modular and reusable styles.

{"import { css } from '@emotion/core';\n\nconst base = css`\n  background: white;\n  color: black;\n`;\n\nconst danger = css`\n  color: red;\n`;\n\nconst DangerButton = () => (\n  <button css={[base, danger]}>\n    Delete\n  </button>\n);"}

Theming

Enables theming support, allowing for styles to be dynamically changed based on a provided theme. This is useful for implementing theme switching in applications.

{"import { ThemeProvider } from 'emotion-theming';\n\nconst theme = {\n  color: 'hotpink'\n};\n\nconst ThemedComponent = () => (\n  <ThemeProvider theme={theme}>\n    <div css={theme => ({\n      color: theme.color\n    })}>\n      This text is hotpink.\n    </div>\n  </ThemeProvider>\n);"}

Other packages similar to @emotion/core

styled-components

Styled-components is a library for React and React Native that allows you to use component-level styles in your application. It uses tagged template literals to style your components. It is similar to @emotion/core in providing a way to write CSS in JS, but styled-components focuses more on component-based styling with a slightly different syntax.

jss

JSS is a CSS-in-JS library that allows you to write CSS in JavaScript. It is framework agnostic and can be used with any JavaScript framework or library. JSS provides a more extensive API for defining styles and supports plugins for extending its capabilities. Compared to @emotion/core, JSS offers more flexibility and control but might have a steeper learning curve.

linaria

Linaria is a zero-runtime CSS-in-JS library that extracts CSS to separate files at build time, resulting in smaller JavaScript bundles. Unlike @emotion/core, which injects styles at runtime, Linaria's approach to extracting static CSS files can lead to better performance for static sites or applications where runtime overhead is a concern.

README

@emotion/core

Simple styling in React.

Install

yarn add @emotion/core

Usage

/** @jsx jsx */
import { jsx, css, Global, ClassNames } from '@emotion/core'

render(
  <div css={{ color: 'hotpink' }}>
    <div
      css={css`
        color: green;
      `}
    />
    <Global
      styles={{
        body: {
          margin: 0,
          padding: 0
        }
      }}
    />
    <ClassNames>
      {({ css, cx }) => (
        <div
          className={cx(
            'some-class',
            css`
              color: yellow;
            `
          )}
        />
      )}
    </ClassNames>
  </div>
)

More documentation is available at https://emotion.sh.