R
fn

useCssVar

v0.0.15testeddemo

Read and write a CSS custom property on an element as a reactive ref. Defaults to `document.documentElement`. Set `observe` to react to external changes via a `MutationObserver`.

Examples

ts
const color = useCssVar('--color', el);
color.value = 'red';
ts
const theme = useCssVar('--theme', null, { initialValue: 'light', observe: true });

Demo

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Signature

ts
export function useCssVar(
  prop: MaybeRefOrGetter<string | null | undefined>,
  target?: MaybeComputedElementRef,
  options: UseCssVarOptions ={ ... }

Parameters

ParameterTypeDescription
propMaybeRefOrGetter<string | null | undefined>The CSS variable name (e.g. `--color`)
target?anyElement to read/write the variable on (defaults to `documentElement`)
options?UseCssVarOptions`initialValue`, `observe`, and a configurable `window`

Returns

UseCssVarReturnA writable ref; reading returns the current value, writing updates the property