How to change the learnr::tutorial output format?

I have seen that the new version of learn 0.10.0 now supports the tabset option. It worked fine after I figured out that I had to include self_contained: true in the YAML header and at the same time I had to remove progressive: true.

Using the tabset option the navigation on the left side is in my opinion not always necessary. I wonder if it is possible to use a modified tutorial template without the left navigation bar but still with the "Start Over" button? I assume that one would need to change the appropriate CSS (tutorial-format.css?) but I do not have the knowledge to do that. Could anyone help me?