how to change the menu items from all uppercase to sentence type?

Ex: HOME = Home

I searched the css-files for "text-transform:". I can only change all the other items (breadcrumbs, article titles, etc) but the menu items.

My Page is running offline on my computer, so I can't give any url.
It looks the same as the AS002066 sample page, since I installed the sample template data.

Thanks for you help!