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CSSPropertyRule: initialValue property

Baseline 2024
Newly available

Since ⁨July 2024⁩, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

The read-only initialValue nullable property of the CSSPropertyRule interface returns the initial value of the custom property registration represented by the @property rule, controlling the property's initial value.

Value

A string which is a <declaration-value>.

Examples

This stylesheet contains a single @property rule. The first CSSRule returned will be a CSSPropertyRule representing this rule. The initialValue property returns the string "#c0ffee" this being the value of the initial-value property in the CSS.

@property --property-name {
  syntax: "<color>";
  inherits: false;
  initial-value: #c0ffee;
}
const myRules = document.styleSheets[0].cssRules;
console.log(myRules[0].initialValue); // "#c0ffee"

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
initialValue 85 85 128 71 16.4 85 128 60 16.4 14.0 85 16.4

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https://developer.mozilla.org/en-US/docs/Web/API/CSSPropertyRule/initialValue