startbootstrap-sb-admin-2/scss/navs/topbar.scss

// Topbar
.topbar {
  height: $topbar-base-height;
  .nav-item {
    .nav-link {
      height: $topbar-base-height;
      display: flex;
      align-items: center;
      padding: 0 0.75rem;
    }
  }
  .dropdown {
    position: static;
    .dropdown-menu {
      width: calc(100% - #{$grid-gutter-width});
      right: $grid-gutter-width / 2;
    }
  }
  @include media-breakpoint-up(md) {
    .dropdown {
      position: relative;
      .dropdown-menu {
        width: auto;
        right: 0;
      }
    }
  }
}

.topbar.navbar-dark {}

.topbar.navbar-light {
  .navbar-nav {
    .nav-item {
      .nav-link {
        color: $gray-400;
        &:hover {
          color: $gray-500;
        }
        &:active {
          color: $gray-600;
        }
      }
    }
  }
}