CSSRuleList.item()

The item() method of the CSSRuleList interface returns the CSSRule object at the specified index or null if the specified index doesn't exist.

index

An integer.

A CSSRule.

In the following example the first item in the CSSRuleList named myRules is printed to the console.

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