Taking out the top level of the drop down menu on mobile view

Hello! I'm new to the community and have been working on a few sites. 
Does anyone know of a way to take out the top level of the drop down menu on mobile view. 
It looks like an extra step to get to the page links in this view. 
Any help you can lend would be much appreciated. 

Add to Design > Custom CSS

/* Show folder on Desktop - Normal nav on mobile */
@media only screen and (max-width: 767px) {
  .header-menu-nav-folder[data-folder="root"] {
    display: none !important;
  }
  .header-menu-nav-folder-content .header-menu-controls {
    display: none;
  }
  .header-menu-nav-folder:not([data-folder="root"]) {
    transform: unset;
    transition: unset;
  }
}

@tuanphan Thank you so much! That worked perfectly! I really appreciate your help. —(G)