CSSPropertyRule: syntax 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 syntax property of the CSSPropertyRule interface returns the literal syntax of the custom property registration represented by the @property rule, controlling how the property's value is parsed at computed-value time.

Value

A string.

Examples

This stylesheet contains a single @property rule. The first CSSRule returned will be a CSSPropertyRule representing this rule. The syntax property returns the literal string "<color>".

css

@property --property-name {
  syntax: "<color>";
  inherits: false;
  initial-value: #c0ffee;
}

let myRules = document.styleSheets[0].cssRules;
console.log(myRules[0].syntax); //the string "<color>"

Specifications

Specification
CSS Properties and Values API Level 1 # dom-csspropertyrule-syntax

Browser compatibility

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