Mobile menu not working

Hi,

I just installed and customised GK Portfolio. It all works great except for the menu. On mobile devices (iOS, Android, even from laptop with resized screen) it does not open. I click on the “menu” button and nothing happens.

I’ve read other threads about it (you mention the js/functions.js file, which I can’t find on my WordPress page), but haven’t managed to fix it.

Could you please help?

Many thanks.