.mailbox-page {
  width: min(768px, 100%);
  margin: 0 auto;
  padding: 36px 24px;
}
.mailbox-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 24px;
}
.mailbox-page a {
  color: var(--brand-strong);
  text-decoration: none;
}
.mailbox-page a:hover { text-decoration: underline; }
.mailbox-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  font-size: 17px;
}
.mailbox-page .mailbox-tool-card {
  width: 100%;
  padding: 28px;
}
.mailbox-page h1 {
  font-size: 24px;
  margin: 0 0 8px;
}
.mailbox-intro {
  margin: 0 0 24px;
  color: var(--muted);
}
.mailbox-form,
.mailbox-fields {
  display: grid;
  gap: 18px;
  min-width: 0;
}
.mailbox-page .form-group { min-width: 0; }
.mailbox-submit {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}
.mailbox-submit .msg { overflow-wrap: anywhere; }
.mailbox-page .mailbox-tool-result { margin-top: 0; }
.mailbox-note {
  margin: 22px 0 0;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}
@media (max-width: 480px) {
  .mailbox-page { padding: 20px 16px; }
  .mailbox-page .mailbox-tool-card { padding: 20px 16px; }
  .mailbox-page h1 { font-size: 22px; }
}