Conditional Styles

Overview

Cerberus allows you to write styles for pseudo states, media queries, and custom data attributes with the conditional style props.

Usage

For example, here's how to change the background color of a button when it's hovered:

<Box bg="danger.bg.initial" _hover={{ bg: "danger.bg.hover" }}>
  Hover me
</Box>

Nested condition

Conditional values can be nested to create complex selector rules.

Here's how to change the background color of an element when in focus on hover:

<Box bg={{ base: "danger.bg.initial", _hover: { _focus: "danger.bg.hover" } }}>
  Hover & Focus me
</Box>

At Rules

This also works with the supported at-rules (@media, @layer, @container, @supports, and @page):

<Box
  css={{
    "@container (min-width: 10px)": {
      color: "success.surface.initial",
    },
  }}
>
  Hello
</Box>

Pseudo Classes

Hover, Active, Focus, and Disabled

Here's an example of how to style the hover, active, focus, and disabled states of an element

<Box
  _hover={{ bg: "danger.bg.hover" }}
  _active={{ bg: "danger.bg.active" }}
  _focus={{ bg: "danger.bg.initial" }}
  _disabled={{ opacity: "0.5" }}
>
  Hover me > Hover me
</Box>

First, Last, Odd, Even

Here's an example of how to style the first, last, odd, and even elements in a list

<ul>
  <For each={items}>
    {(item) => (
      <li key={item}>
        <Box
          _first={{ color: "danger.bg.initial" }}
          _last={{ color: "red.800" }}
        >
          {item}
        </Box>
      </li>
    )}
  </For>
</ul>

You can also style even and odd elements using the _even and _odd modifier

<Table.Root>
  <Table.Body>
    <For each={items}>
    {(item) => (
      <Table.Row key={item} css={{
        _even={{ bg: "gray.100" }}
        _odd={{ bg: "white" }}
      }}>
        <Table.Cell>{item}</Table.Cell>
      </Table.Row>
    )}
  </Table.Body>
</Table.Root>

Pseudo Elements

Before and After

To style the ::before and ::after pseudo elements of an element, use the _before and _after modifiers

<Box _before={{ content: '"👋"' }} _after={{ content: '"🥂"' }}>
  Hello
</Box>

Placeholder

To style the placeholder text of any input or textarea, use the _placeholder modifier:

<Input
  placeholder="Enter your name"
  css={{
    _placeholder={{ color: "gray.500" }}
  }}
/>

File Inputs

To style the file input button, use the _file modifier:

<Input
  type="file"
  css={{
    _file={{ bg: "gray.500", px: "4", py: "2", marginEnd: "3" }}
  }}
/>

Media Queries

Reduced Motion

Use the _motionReduce and _motionSafe modifiers to style an element based on the user's motion preference:

<Box _motionSafe={{ transition: "all 0.3s" }}>Hello</Box>

Color Scheme

The prefers-color-scheme media feature is used to detect if the user has requested the system to use a light or dark color theme.

Use the _osLight and _osDark modifiers to style an element based on the user's color scheme preference:

<Box bg={{ base: "white", _osDark: "black" }}>Hello</Box>

Color Contrast

The prefers-contrast media feature is used to detect if the user has requested the system use a high or low contrast theme.

Use the _highContrast and _lessContrast modifiers to style an element based on the user's color contrast preference:

<Box bg={{ base: "white", _highContrast: "black" }}>Hello</Box>

Orientation

The orientation media feature is used to detect if the user has a device in portrait or landscape mode.

Use the _portrait and _landscape modifiers to style an element based on the user's device orientation:

<Box pb="4" _portrait={{ pb: "8" }}>
  Hello
</Box>

Selectors

Arbitrary selectors

For arbitrary, use the css prop to write styles for one-off selectors:

<Box css={{ "&[data-state=closed]": { color: "red.300" } }} />

Here's another example that targets the child elements of a parent element:

<Box
  css={{
    "& > *": { margin: "2" },
  }}
/>

Group Selectors

To style an element based on its parent element's state or attribute, add the group class to the parent element, and use any of the _group* modifiers on the child element.

<div className="group">
  <Text _groupHover={{ bg: "danger.bg.initial" }}>Hover me</Text>
</div>

This modifier works for every pseudo class modifiers like _groupHover, _groupActive, _groupFocus, and _groupDisabled, etc.

Sibling Selectors

To style an element based on its sibling element's state or attribute, add the peer class to the sibling element, and use any of the _peer* modifiers on the target element.

<div>
  <p className="peer">Hover me</p>
  <Box _peerHover={{ bg: "danger.bg.initial" }}>I'll change by bg</Box>
</div>

Note: This only works for when the element marked with peer is a previous siblings, that is, it comes before the element you want to start.

Data Attribute

LTR and RTL

To style an element based on the direction of the text, use the _ltr and _rtl modifiers

<div dir="ltr">
  <Box _ltr={{ ml: "3" }} _rtl={{ mr: "3" }}>
    Hello
  </Box>
</div>

State

To style an element based on its data-{state} attribute, use the corresponding _{state} modifier

<Box data-state="indeterminate" _indeterminate={{ bg: "gray.500" }}>
  Hello
</Box>

This works for common states like data-active, data-disabled, data-focus, data-hover, data-invalid, data-required, and data-valid.

<Box data-active _active={{ bg: "gray.500" }}>
  Hello
</Box>

Orientation

To style an element based on its data-orientation attribute, use the _horizontal and _vertical modifiers

<Box
  data-orientation="horizontal"
  _horizontal={{ bg: "danger.bg.initial" }}
  _vertical={{ bg: "action.bg.initial" }}
>
  Hello
</Box>

ARIA Attribute

To style an element based on its aria-{state}=true attribute, use the corresponding _{state} prop

<Box aria-expanded="true" _expanded={{ bg: "gray.500" }}>
  Hello
</Box>

Reference

Here's a list of all the condition props you can use in Cerberus:

Cerberus extends the built-in conditions provided by Panda-CSS.

Customization

Cerberus lets you create your own conditions, so you're not limited to the ones in the default preset. Learn more about customizing conditions here.