metamask-extension/ui/components/app/menu-bar/index.scss

.menu-bar {
  display: grid;
  grid-template-columns: 30% minmax(30%, 1fr) 30%;
  column-gap: 5px;
  padding: 0 8px;
  border-bottom: 1px solid var(--color-border-muted);
  height: 64px;

  .menu-bar__account-options {
    background: none;
    font-size: inherit;
    padding: 0 8px 0 5px;
    place-self: center end;
    color: var(--color-text-default);
  }

  .selected-account {
    grid-column: 2 / span 1;
    place-self: center stretch;
  }
}

.account-options-menu {
  &__explorer-origin {
    @include H7;

    color: var(--color-text-alternative);
  }
}