Vertical quiz-summary navigation

The quiz-summary navigation is ugly in my quiz.
It’s not like the pop-up example image in settings or the demo quiz in your blog,
the number buttons are displayed vertically.

http://widyagama.ac.id/informatika/wp-content/uploads/2014/02/vertical-quiz-summary-navigation.png

This happens in all browsers.
Oh_ what should I do?

https://wordpress.org/plugins/wp-pro-quiz/