If you want to make the list inline you have to change the .less files.
Here is how you get started with less: Getting started with LESS
And how to get started to modify your templates: Getting started with Shopware templating
And here are the lines for this menu, its in the header.less : shopware/header.less at 679aad0aa1e59c1f677aca65d894a2d17007c3d1 · shopware/shopware · GitHub