public function setTitle($prefix)
    {
        $this->addHook(function($document) use ($prefix) {
            $title = $document->getTitle();

            if ($title) {
                $title = $prefix . ' - ' . $title;
            } else {
                $title = $prefix;
            }

            $document->addHeaderNode(new RawNode('<title>'.htmlspecialchars($title).'</title>'));
        });

        return $this;
    }