Highend Theme: Mobile Site too simplified compared to main site.

I am using the Highend theme. I am very happy with the desktop view. However, the mobile version of the website is too zoomed in, or narrow. Everything looks big, and makes navigation difficult. The tablet view is a bit better. But I still would like it wider.

I have tried going to appearance to change it but it is not possible without changing the theme.

Is there a setting to adjust the zoom on different devices to make the appearance look better?