public function elementShouldNotHaveClass($selector, $class)
    {
        $session = $this->getSession();
        $page = $session->getPage();
        $element = $page->find('css', $selector);

        if (!$element) {
            throw new ElementNotFoundException($session, 'Element "'.$selector.'"');
        }

        \PHPUnit_Framework_TestCase::assertFalse($element->hasClass($class));
    }