I don’t like the standard 768 cutoff for mobile. I would prefer to set mobile at 650. I was able to override most of this in my child theme CSS file so I can delay generation of the hamburger menu until 650.
But… the inline CSS generated by css-output.php (and other files) is a pain to deal with because it changes my header pixel height and site title, amongst other things, at 768.
This occurs in the css-ouput.php file at lines 458 and 510 in the code. But 768 is also generated elsewhere in the inline css. What’s the best solution for this so that the WP customizer still works and I don’t go hacking the main theme code? The only thing I can think of is for your team to hardcode a menu option in the customizer for max-width.