Concepts

Template Literals

Panda allows you use the template literal syntax (opens in a new tab) as an alternative to the object literal syntax.

This provides a similar experience to styled-components (opens in a new tab) and emotion (opens in a new tab), except that Panda generates atomic class names instead of a single unique class name.

💡

Emitting atomic class names allows Panda to generate smaller CSS bundles.

Panda provides two function to write template literal styles, css and styled.

Getting started

To use template literals, you need to set the syntax option in your panda.config.ts file to templateLiteral:

// panda.config.ts
export default defineConfig({
  // ...
  syntax: 'template-literal', // required
  jsxFramework: 'react' // optional
})

Then run the codegen command to generate the functions:

panda codegen --clean

The css function

This the basic way of writing template styles. It converts the template literal into a set of atomic class name which you can pass to the className prop of an element.

import { css } from '../styled-system/css'
 
const className = css`
  font-size: 16px;
  font-weight: bold;
`
 
function Heading() {
  return <h1 className={className}>This is a title</h1>
}
 
// => <h1 className='font-size_16px font-weight_bold'></h1>

Here's what the emitted atomic CSS looks like:

.font-size_16px {
  font-size: 16px;
}
 
.font-weight_bold {
  font-weight: bold;
}

The styled tag

The styled tag allows you to create a component with encapsulated styles. It's similar to the styled-components or emotion library.

import { styled } from '../styled-system/jsx'
 
// Create a styled component
const Heading = styled.h1`
  font-size: 16px;
  font-weight: bold;
`
 
function Demo() {
  // Use the styled component
  return <Heading>This is a title</Heading>
}
 
// => <h1 class='font-size_16px font-weight_bold'>This is a title</h1>

Here's what the emitted atomic CSS looks like:

.font-size_16px {
  font-size: 16px;
}
 
.font-weight_bold {
  font-weight: bold;
}

Nested styles

You can nest selectors, pseudo-elements and pseudo-selectors.

const Button = styled.button`
  color: black;
 
  &:hover {
    color: blue;
  }
`

Using css nesting syntax, pseudo-elements, pseudo-selectors and combinators are also supported:

const Demo = styled.div`
  color: black;
 
  &::after {
    content: '🐼';
  }
 
  & + & {
    background: yellow;
  }
 
  &.bordered {
    border: 1px solid black;
  }
 
  .parent & {
    color: red;
  }
`

Nested media and container queries are also supported:

const Demo = styled.div`
  color: black;
 
  @media (min-width: 200px) {
    color: blue;
  }
 
  @container (min-width: 200px) {
    color: red;
  }
`

Hashing class names

In some cases, it might be useful to shorten the class names by hashing them. Set the hash: true option in your panda.config.ts file to enable this. This will generate shorter class names but will make it harder to debug.

To achieve this, set the hash option in your panda.config.ts file to true:

// panda.config.ts
 
export default defineConfig({
  // ...
  hash: true // optional
})
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Run the codegen command to regenerate the functions with hashing enabled.

When hashing is enabled, the class names will go from this:

.font-size_16px {
  font-size: 16px;
}
 
.font-weight_bold {
  font-weight: bold;
}

To a unique six character hash regardless of the length of the selector or the number of declarations:

.adfg5r {
  font-size: 16px;
}
 
.bsdf35 {
  font-weight: bold;
}

Using tokens

Use the token() function or {} syntax in your template literals to reference design tokens in your styles. Panda will automatically generate the corresponding CSS variables.

import { css } from '../styled-system/css'
 
const className = css`
  font-size: {fontSizes.md};
  font-weight: token(fontWeights.bold, 700);
`

Caveats

The object literal syntax is the recommended way of writing styles. But, if you stick with the template literal syntax, there are some caveats to be aware of:

  • Patterns and recipes are not generated
  • Dynamic interpolation or component targeting is not supported
  • Lack of autocompletion for tokens within the template literal Our Eslint plugin (opens in a new tab) can help you overcome this by detecting invalid tokens
  • JSX Style props are not supported