"hamburger" mobile nav icon click event : changing breakpoint of mobile menu display

[mlclm]

Clicking the "hamburger" icon ( Mobile menu icon ) ( div id="menu-icon") : adds a class to header like so : "is-open" , but it also adds all the links inside "mobile_top_menu_wrapper" , this looks like it is added with the help of some javascript.

I want to show the mobile navigation below 1200px. I could edit css files to have the icon show but the menu does not display when I click on the "hamburger" icon.

After looking on Google, the file theme.js , maybe needs to be changed for my need , with "u.default.responsive.min_width" - I tried but this changes some elements in the header to show up or not depending on the display. Not sure if I should touch this.

Could anyone point me in the right direction ? I want to have the links show up inside the " mobile_top_menu_wrapper " below 1200px.   Not just below 576px;

Thanks