CSSGroupingRule: cssRules property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2015.

The cssRules property of the CSSGroupingRule interface returns a CSSRuleList containing a collection of CSSRule objects.

let myRules = document.styleSheets[0].cssRules;
console.log(myRules);

Specification
CSS Object Model (CSSOM) # dom-cssgroupingrule-cssrules

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