styled-components.com/docs/basics

Starting URLs:
https://styled-components.com/docs/basics
## Page: https://styled-components.com/docs/basics

## Motivation

**styled-components is the result of wondering how we could enhance CSS for styling React component systems.** By focusing on a single use case we managed to optimize the experience for developers as well as the output for end users.

Apart from the improved experience for developers, styled-components provides:

*   **Automatic critical CSS**: styled-components keeps track of which components are rendered on a page and injects their styles and nothing else, fully automatically. Combined with code splitting, this means your users load the least amount of code necessary.
*   **No class name bugs**: styled-components generates unique class names for your styles. You never have to worry about duplication, overlap or misspellings.
*   **Easier deletion of CSS**: it can be hard to know whether a class name is used somewhere in your codebase. styled-components makes it obvious, as every bit of styling is tied to a specific component. If the component is unused (which tooling can detect) and gets deleted, all its styles get deleted with it.
*   **Simple dynamic styling**: adapting the styling of a component based on its props or a global theme is simple and intuitive without having to manually manage dozens of classes.
*   **Painless maintenance**: you never have to hunt across different files to find the styling affecting your component, so maintenance is a piece of cake no matter how big your codebase is.
*   **Automatic vendor prefixing**: write your CSS to the current standard and let styled-components handle the rest.

You get all of these benefits while still writing the CSS you know and love, just bound to individual components.

## Installation

Installing styled-components only takes a single command and you're ready to roll:

    # with npm
    npm install styled-components
    
    # with yarn
    yarn add styled-components
    

If you use a package manager like yarn that supports the "resolutions" package.json field, we also highly recommend you add an entry to it as well corresponding to the major version range. This helps avoid an entire class of problems that arise from multiple versions of styled-components being installed in your project.

In `package.json`:

{
  "resolutions": {
    "styled-components": "^5"
  }
}

**Note**

It's highly recommended (but not required) to also use the Babel plugin. It offers many benefits like more legible class names, server-side rendering compatibility, smaller bundles, and more.

Click here to see alternative CDN installation instructions

If you're not using a module bundler or package manager we also have a global ("UMD") build hosted on the unpkg CDN. Simply add the following `<script>` tag to the bottom of your HTML file:

<script src\="https://unpkg.com/styled-components/dist/styled-components.min.js"\></script\>

Once you've added `styled-components` you will have access to the global `window.styled` variable.

const Component \= window.styled.div\`
  color: red;
\`

## Getting Started

`styled-components` utilises tagged template literals to style your components.

It removes the mapping between components and styles. This means that when you're defining your styles, you're actually creating a normal React component, that has your styles attached to it.

This example creates two simple components, a wrapper and a title, with some styles attached to it:

## Hello World!

This is a live editor, so play around with the code to get a feel for what it's like to work with styled-components!

**Note**

The CSS rules are automatically vendor prefixed, styled-components takes care of that for you!

Styled components uses stylis.js package under the hood for prefixing the css rules.

For additional information about the supported prefixes in stylis.js visit their repository.

## Adapting based on props

You can pass a function ("interpolations") to a styled component's template literal to adapt it based on its props.

This button component has a primary state that changes its color. When setting the `$primary` prop to true, we are swapping out its background and text color.

## Extending Styles

Quite frequently you might want to use a component, but change it slightly for a single case. Now, you could pass in an interpolated function and change them based on some props, but that's quite a lot of effort for overriding the styles once.

To easily make a new component that inherits the styling of another, just wrap it in the `styled()` constructor. Here we use the button from the last section and create a special one, extending it with some color-related styling:

We can see that the new `TomatoButton` still resembles `Button`, while we have only added two new rules.

In some cases you might want to change which tag or component a styled component renders. This is common when building a navigation bar for example, where there are a mix of anchor links and buttons but they should be styled identically.

For this situation, we have an escape hatch. You can use the `"as" polymorphic prop` to dynamically swap out the element that receives the styles you wrote:

This works perfectly fine with custom components too!

## Styling any component

The `styled` method works perfectly on all of your own or any third-party component, as long as they attach the passed `className` prop to a DOM element.

**Note**

If you are using `react-native` keep in mind to use `style` instead of `className`.

**Note**

You can also pass tag names into the `styled()` factory call, like so: `styled("div")`. In fact, the `styled.tagname` helpers are just aliases that do the same.

## Passed props

If the styled target is a simple element (e.g. `styled.div`), styled-components passes through any known HTML attribute to the DOM. If it is a custom React component (e.g. `styled(MyComponent)`), styled-components passes through all props.

This example shows how all props of the Input component are passed on to the DOM node that is mounted, as with React elements.

Note how the `$inputColor` prop is not passed to the DOM, but `type` and `defaultValue` are? The `styled` function is smart enough to filter non-standard attributes automatically for you.

## Coming from CSS

### How do Styled Components work within a component?

If you're familiar with importing CSS into your components (e.g. like CSSModules) you'll be used to doing something like this:

import React from 'react';
import styles from './styles.css';
export default class Counter extends React.Component {
  state \= { count: 0 };
  increment \= () \=> this.setState({ count: this.state.count + 1 });
  decrement \= () \=> this.setState({ count: this.state.count \- 1 });
  render() {
    return (
      <div className\={styles.counter}\>
        <p className\={styles.paragraph}\>{this.state.count}</p\>
        <button className\={styles.button} onClick\={this.increment}\>
          +
        </button\>
        <button className\={styles.button} onClick\={this.decrement}\>
          \-
        </button\>
      </div\>
    );
  }
}

Because a Styled Component is the _combination_ of the element and the rules that style it, we'd write `Counter` like this:

import React from 'react';
import styled from 'styled-components';
const StyledCounter \= styled.div\`
  /\* ... \*/
\`;
const Paragraph \= styled.p\`
  /\* ... \*/
\`;
const Button \= styled.button\`
  /\* ... \*/
\`;
export default class Counter extends React.Component {
  state \= { count: 0 };
  increment \= () \=> this.setState({ count: this.state.count + 1 });
  decrement \= () \=> this.setState({ count: this.state.count \- 1 });
  render() {
    return (
      <StyledCounter\>
        <Paragraph\>{this.state.count}</Paragraph\>
        <Button onClick\={this.increment}\>+</Button\>
        <Button onClick\={this.decrement}\>\-</Button\>
      </StyledCounter\>
    );
  }
}

Note that we added a "Styled" prefix to `StyledCounter` so that the React component `Counter` and the Styled Component `StyledCounter` don't clash names but remain easily identifiable in the React Developer Tools and Web Inspector.

### Define Styled Components outside of the render method

It is important to define your styled components outside of the render method, otherwise it will be recreated on every single render pass. Defining a styled component within the render method will thwart caching and drastically slow down rendering speed, and should be avoided.

Write your styled components the recommended way:

const StyledWrapper \= styled.div\`
  /\* ... \*/
\`;
const Wrapper \= ({ message }) \=> {
  return <StyledWrapper\>{message}</StyledWrapper\>;
};

Instead of:

const Wrapper \= ({ message }) \=> {
  
  const StyledWrapper \= styled.div\`
    /\* ... \*/
  \`;
  return <StyledWrapper\>{message}</StyledWrapper\>;
};

**Recommended reading**: Talia Marcassa wrote a great review of real-world usage, featuring lots of solid practical insights and comparisons with alternatives, in Styled Components: To Use or Not to Use?

### Pseudoelements, pseudoselectors, and nesting

The preprocessor we use, stylis, supports scss-like syntax for automatically nesting styles.

Through this preprocessing, styled-components supports some advanced selector patterns:

*   `&` a single ampersand refers to **all instances** of the component; it is used for applying broad overrides:
    
    Hello world!
    
    How ya doing?
    
    The sun is shining...
    
    Pretty nice day today.
    
    Don't you think?
    
    Splendid.
    
*   `&&` a double ampersand refers to **an instance** of the component; this is useful if you're doing conditional styling overrides and don't want a style to apply to _all instances_ of a particular component:
    
    FooFooFooFoo
    
*   `&&` a double ampersand alone has a special behavior called a "precedence boost"; this can be useful if you are dealing with a mixed styled-components and vanilla CSS environment where there might be conflicting styles:
    
    I'm blue, da ba dee da ba daa
    

If you put selectors in without the ampersand, they will refer to children of the component.

Mystery button

## Attaching additional props

v2

To avoid unnecessary wrappers that just pass on some props to the rendered component or element, you can use the `.attrs` constructor. It allows you to attach additional props (or "attributes") to a component.

This way you can for example attach static props to an element or pass a third-party prop like `activeClassName` to React Router's Link component. Furthermore, you can also attach more dynamic props to a component. The `.attrs` object also takes functions, that receive the props that the component receives. The return value will be merged into the resulting props as well.

Here we render an `Input` component and attach some dynamic and static attributes to it:

As you can see, we get access to our newly created props in the interpolations, and the `type` attribute is passed down to the element.

### Overriding .attrs

Notice that when wrapping styled components, `.attrs` are applied from the innermost styled component to the outermost styled component.

This allows each wrapper to **override** nested uses of `.attrs`, similarly to how CSS properties defined later in a stylesheet override previous declarations.

`Input`'s `.attrs` are applied first, and then `PasswordInput`'s `.attrs`:

This is why `PasswordInput` is of a `'password'` type, but still uses the `$size` attribute from `Input`.

## Animations

CSS animations with `@keyframes` aren't scoped to a single component but you still don't want them to be global to avoid name collisions. This is why we export a `keyframes` helper which will generate a unique instance that you can use throughout your app:

< 💅🏾 >

Keyframes are lazily injected when they're used, which is how they can be code-split, so you have to use the `css` helper for shared style fragments:

const rotate \= keyframes\`\`
const styles \= \`
  animation: ${rotate} 2s linear infinite;
\`
const styles \= css\`
  animation: ${rotate} 2s linear infinite;
\`

**Note**

This used to work in v3 and below where we didn't code-split keyframes. If you're upgrading from v3, make sure that all your shared style fragments are using the `css` helper!

## React Native

styled-components can be used with React Native in the same way and with the same import. Try this example with Snack by Expo.

import React from 'react'
import styled from 'styled-components/native'
const StyledView \= styled.View\`
  background-color: papayawhip;
\`
const StyledText \= styled.Text\`
  color: #BF4F74;
\`
class MyReactNativeComponent extends React.Component {
  render() {
    return (
      <StyledView\>
        <StyledText\>Hello World!</StyledText\>
      </StyledView\>
    )
  }
}

We also support more complex styles (like `transform`), which would normally be an array, and shorthands (e.g. for `margin`) thanks to `css-to-react-native`!

**Note**

Note that the `flex` property works like CSS shorthand, and not the legacy `flex` property in React Native. Setting `flex: 1` sets `flexShrink` to `1` in addition to setting `flexGrow` to `1` and `flexBasis` to `0`.

Imagine how you'd write the property in React Native, guess how you'd transfer it to CSS, and you're probably right:

const RotatedBox \= styled.View\`
  transform: rotate(90deg);
  text-shadow-offset: 10px 5px;
  font-variant: small-caps;
  margin: 5px 7px 2px;
\`

Some of the differences to the web-version are, that you cannot use the `keyframes` and `createGlobalStyle` helpers since React Native doesn't support keyframes or global styles. We will also warn you if you use media queries or nest your CSS.

**Note**

In v2 we support percentages. To make this possible we need to enforce units for all shorthands. If you're migrating to v2, a codemod is available.

### Simpler usage with the metro bundler

If you'd prefer to just import `styled-components` instead of `styled-components/native`, you can add a `resolverMainFields` configuration that includes `"react-native"`. This used to be supported in metro by default (and currently does work in haul) but appears to have been removed at some point.

### Continue on the next page

## Advanced