Button theme: keep right sidebar on mobile device or tablet

Hi,

I am using the button theme. On my mobile phone and tablet, the right sidebar is moving below the contents. How can I adjust this? Also on mobile devices I would like to see the sidebar at the right side.

My mediaquaries are as follows:

[Large code excerpt removed by moderator per forum rules. Please use Pastebin or a Gist for all large code excerpts, they work better anyway.]

Hopefully you can help me. Thanks!