Tabbed menu help?

Hi guys,

I'm not sure if it's a bug or if it's because I'm using an outdated version of forum themes/tabbed menu (I'm using mybb1.8.7).

But, the tabbed menu isn't showing as I want it too, compared to how they show on other sites. Can anyone quickly provide assistance to a fix?

https://i.imgur.com/Z6qbZFC.png

https://i.imgur.com/Twb1N0o.png

Regards
Maedrys