metamask-extension/ui/components/app/transaction-status/index.scss

.transaction-status {
  display: inline;

  &--unapproved {
    color: $Orange-500;
  }

  &--failed {
    color: $Red-500;
  }

  &--cancelled {
    color: $Red-500;
  }

  &--dropped {
    color: $Red-500;
  }

  &--rejected {
    color: $Red-500;
  }

  &--pending {
    color: $Orange-500;
  }

  &--queued {
    color: $Grey-500;
  }
}