Emir

I’m using someone elses Navwalker for the menu (https://github.com/Poruno/Bulma-Navwalker), and it’s not supposed to do that.
If you want to automatically show child items on mobile try something like this:

@media screen and (max-width: 1088px) {
.navbar-item .navbar-dropdown {
display: block;
}
}

Hm, I just tested it and it works for me. See here https://imgur.com/4zJE4lh

Did you forgot to add “fancybox-youtube” class?
(In case CSS Classes box is hidden for you go to “Screen options” in the upper right corner and tick CSS Classes)