discourse-header-submenus/desktop/desktop.scss

.vmo {
  display: none;
}

@if $Fixed_mode == "true" {
  .d-dropdown {
    top: 38.5px !important;
  }
  .d-header {
    margin-top: 38.5px;
  }
  .top-menu {
    position: fixed;
    width: 100%;
    z-index: z("header") + 1;
  }
  #main-outlet {
    padding-top: 8.65em;
  }
}