Just give your button/element the class “grve-toggle-responsive-menu”. As a link, just insert “#” (or anything which fits to you best, e.g. “#hidden-menu”).
Keep in mind that you need to add a close button with the class “grve-close-btn”, if you don’t use the fullscreen responsive menu (the one where the header keeps visible).
Also increase the z-index of the menu area from 3 to 7 to hide the main header on desktop mode.
