The CSSStyleRule interface represents a single CSS style rule.

Inherits properties from its ancestor CSSRule.

CSSStyleRule.selectorText

Returns the textual representation of the selector for this rule, e.g. "h1,h2".

CSSStyleRule.style Read only

Returns the CSSStyleDeclaration object for the rule.

CSSStyleRule.styleMap Read only

Returns a StylePropertyMap object which provides access to the rule's property-value pairs.

No specific methods; inherits methods from its ancestor CSSRule.

The CSS includes one style rule. This will be the first CSSRule returned by document.styleSheets[0].cssRules. myRules[0] therefore returns a CSSStyleRule object representing the rule defined for h1.

h1 {
  color: pink;
}

let myRules = document.styleSheets[0].cssRules;
console.log(myRules[0]); // a CSSStyleRule representing the h1.