Changing order of main nav

Is there a way to change the order of the links in the main navigation bar?

My site can be found here: https://180.a6f.myftpupload.com/

I’d like the order to be as follows: home. gallery. about. contact.

I see I could reorder the list items, but I’m not sure how to access the html.

Thank you! Really liking this template.