code: function (config) {
      this.idPrefix = config.idPrefix || 'kss-fullscreen-';
      this.bodyClass = config.bodyClass || 'kss-fullscreen-mode';
      this.elementClass = config.elementClass || 'is-fullscreen';
  
      this.init();
    }
docs: Set the configuration values on object creation. - idPrefix: The string that uniquely prefixes the ID of all elements that can receive the fullscreen focus. - bodyClass: The class that is set on the body element when the fullscreen mode is toggled on. - elementClass: the class that is set on the element that is receiving the fullscreen focus.