The CSSFontFaceRule interface represents an @font-face at-rule.

Inherits properties from its ancestor CSSRule.

CSSFontFaceRule.style Read only

Returns a CSSStyleDeclaration.

Inherits methods from its ancestor CSSRule.

This example uses the CSS found as an example on the @font-face page. The first CSSRule returned will be a CSSFontFaceRule.

@font-face {
  font-family: MyHelvetica;
  src: local("Helvetica Neue Bold"), local("HelveticaNeue-Bold"),
    url(MgOpenModernaBold.ttf);
  font-weight: bold;
}

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