Orvis Theme, Sidebar display order

Hi,

I’m using Orvis on a self-hosted site. All good, but……

I would like to be able to display info in the sidebar before main content when viewing on a mobile device. At present, all content displays first, and once at the bottom of the page we see the sidebar content. As I’m putting custom menus in the sidebar often, I’d like them to display first when on mobile. Also, it would be great to be able to affect this on a page-by-page basis with custom CSS for each page. I have a plugin running for this.

Here’s a link:
https://www.100hands.org/sarahwilkins/editorial/

Thanks for any help.