@media (max-width: 680px) {
  #private-brief.private-brief form > footer { flex-direction: column; align-items: stretch; gap: 12px; }
  #private-brief.private-brief form > footer > div:empty { display: none; }
  #private-brief.private-brief form > footer button { min-width: 0; width: 100%; overflow-wrap: anywhere; }
}