Overleaf/services/web/frontend/stylesheets/components/button-group.scss

.btn-group {
  > .btn {
    &:first-of-type {
      padding-left: var(--spacing-05);
    }

    &:last-of-type {
      padding-right: var(--spacing-05);
    }
  }
}

.btn-toolbar {
  gap: var(--spacing-03);
  flex-wrap: nowrap;
}