Content to Sidebar ratio 7:3 ?

Hi all,

I am using this theme but I am having problems setting up the layout so that sidebar is on the right side and takes 30% of the container and content takes up 70%.

According to setting – it should have been one sidebar on the right side of the screen but it seems that there are 2 layout columns and ratio is 50:25:25.

Any ideas how can I get layout of 70:30 with content and one sidebar respectively?

Screens:
https://i.imgur.com/vW5ExiC.png
https://i.imgur.com/QYUklw9.png

Website:
https://therunawaydude.com/

I want it to look precisely as in demo: https://demo.onedesigns.com/pinboard/?page_id=8