public function classes() {

		$classes = array(
			'toggle-checkbox',
		);

		if ( ! empty( $this->struct['on_icon'] ) ) {
			$this->icons['on'] = $this->struct['on_icon'];
		}

		if ( ! empty( $this->struct['off_icon'] ) ) {
			$this->icons['off'] = $this->struct['off_icon'];
		}

		return $classes;
	}