Responsive HTML - changing desktop>tablet breakpoint

I am trying to change at pixel width at which desktop view changes to tablet and therefore when the sidebar switches to icons.

It seems Javascript is used to remove sidebar-opened class from various divs when screen is reduced below 1300px. I need to change this value to 1200px.

I could add responsive CSS to do this but it would be much easier to update the JS. I narrowed this down to the one of the scripts responsible for this to script \Responsive_HTML5\template\scripts\rh.min.js but I couldn't understand how it adds/removes 'sidebar-opened' going between desktop/tablet.

Anyone have any strategies or options?

Thanks,

Daniel

RoboHelp 2015