.postbox-page {
  position: relative;
  display: grid;
  grid-template-rows: minmax(0, 1fr);
  height: calc(100vh - 115px);
  min-height: 0;
  overflow: hidden;
  padding: 0;
  color: var(--text);
  background: var(--bg);
}

.postbox-page *,
.postbox-page *::before,
.postbox-page *::after,
.postbox-admin-page *,
.postbox-admin-page *::before,
.postbox-admin-page *::after {
  box-sizing: border-box;
}

.postbox-shell {
  min-width: 0;
  min-height: 0;
  display: grid;
  grid-template-columns:
    minmax(250px, 310px)
    minmax(290px, 370px)
    minmax(360px, 1fr);
  height: 100%;
  overflow: hidden;
  background: var(--panel);
}

.postbox-directory,
.postbox-message-list,
.postbox-detail {
  min-width: 0;
  min-height: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--panel);
}

.postbox-directory,
.postbox-message-list {
  border-right: var(--border-line);
}

.postbox-directory {
  background: var(--panel-soft);
}

.postbox-bar-title,
.postbox-icon-actions,
.postbox-scope-row,
.postbox-item-title,
.postbox-message-heading,
.postbox-message-meta,
.postbox-detail-status,
.postbox-detail-byline,
.postbox-access-explanation,
.postbox-attachments > div,
.postbox-participants > div {
  display: flex;
  align-items: center;
}

.postbox-bar-title {
  min-width: 0;
  gap: 8px;
  color: var(--text-strong);
}

.postbox-bar-title strong {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.postbox-icon-actions {
  gap: 5px;
}

.postbox-scope-control {
  flex: 0 0 auto;
  border-bottom: var(--border-line);
  padding: 9px 10px;
}

.postbox-scope-control > label {
  display: block;
  margin-bottom: 5px;
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
}

.postbox-scope-row {
  gap: 6px;
}

.postbox-scope-row select {
  min-width: 0;
  flex: 1;
}

.postbox-directory-list,
.postbox-messages {
  min-height: 0;
  overflow: auto;
  padding: 7px;
}

.postbox-directory-list,
.postbox-messages {
  flex: 1 1 auto;
}

.postbox-message-filters {
  flex: 0 0 auto;
  display: grid;
  gap: 7px;
  border-bottom: var(--border-line);
  padding: 8px 9px;
}

.postbox-search-row {
  width: 100%;
}

.postbox-search-row input {
  min-width: 0;
  flex: 1;
}

.postbox-message-list > .data-grid-pagination {
  flex: 0 0 auto;
  flex-wrap: wrap;
  gap: 7px 12px;
  border-top: var(--border-line);
}

.postbox-message-list > .data-grid-pagination .data-grid-page-controls {
  width: 100%;
  justify-content: center;
}

.postbox-directory-list .selection-list,
.postbox-messages .selection-list,
.postbox-admin-list .selection-list {
  gap: 4px;
}

.postbox-directory-item,
.postbox-message-item,
.postbox-admin-list .selection-list-item {
  display: grid;
  min-height: 64px;
  gap: 4px;
  align-content: center;
  text-align: left;
}

.postbox-item-title,
.postbox-message-heading {
  min-width: 0;
  justify-content: space-between;
  gap: 10px;
}

.postbox-item-title strong,
.postbox-message-heading strong {
  min-width: 0;
  overflow: hidden;
  color: var(--text-strong);
  text-overflow: ellipsis;
  white-space: nowrap;
}

.postbox-item-context,
.postbox-item-address,
.postbox-message-preview,
.postbox-message-meta {
  min-width: 0;
  overflow: hidden;
  color: var(--muted);
  font-size: 12px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.postbox-message-item.is-read strong {
  font-weight: 550;
}

.postbox-message-item.is-unread strong {
  font-weight: 800;
}

.postbox-message-heading time {
  flex: 0 0 auto;
  color: var(--muted);
  font-size: 11px;
}

.postbox-message-meta {
  justify-content: flex-start;
  gap: 10px;
}

.postbox-message-meta span {
  display: inline-flex;
  min-width: 0;
  align-items: center;
  gap: 3px;
}

.postbox-message-list > .alert {
  flex: 0 0 auto;
  margin: 8px 10px 0;
}

.postbox-message-detail {
  min-height: 0;
  overflow: auto;
  padding: 20px 24px 28px;
}

.postbox-message-detail > header,
.postbox-provenance,
.postbox-body,
.postbox-participants,
.postbox-attachments {
  border-bottom: var(--border-line);
  padding-bottom: 18px;
  margin-bottom: 18px;
}

.postbox-detail-status {
  flex-wrap: wrap;
  gap: 6px;
}

.postbox-message-detail h1 {
  max-width: 900px;
  margin: 12px 0 9px;
  color: var(--text-strong);
  font-size: 24px;
  font-weight: 650;
  overflow-wrap: anywhere;
}

.postbox-detail-byline {
  justify-content: space-between;
  gap: 12px;
  color: var(--muted);
  font-size: 12px;
}

.postbox-provenance h2,
.postbox-participants h2,
.postbox-attachments h2 {
  margin: 0 0 10px;
  color: var(--text-strong);
  font-size: 14px;
}

.postbox-provenance dl,
.postbox-admin-properties {
  display: grid;
  grid-template-columns: repeat(2, minmax(170px, 1fr));
  gap: 10px 18px;
  margin: 0;
}

.postbox-provenance dt,
.postbox-admin-properties dt {
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
}

.postbox-provenance dd,
.postbox-admin-properties dd {
  min-width: 0;
  margin: 3px 0 0;
  overflow-wrap: anywhere;
}

.postbox-body p {
  max-width: 900px;
  margin: 0;
  line-height: 1.6;
  white-space: pre-wrap;
}

.postbox-participants,
.postbox-attachments {
  display: grid;
  gap: 7px;
}

.postbox-participants > div,
.postbox-attachments > div {
  justify-content: flex-start;
  gap: 10px;
  border: var(--border-line);
  border-radius: var(--radius-sm);
  background: var(--surface);
  padding: 9px 10px;
}

.postbox-participants > div strong {
  min-width: 90px;
  color: var(--muted);
  font-size: 11px;
  text-transform: uppercase;
}

.postbox-attachments > p {
  margin: 0;
  color: var(--muted);
}

.postbox-attachments > div span {
  min-width: 0;
  display: grid;
  gap: 2px;
}

.postbox-attachments > div strong,
.postbox-attachments > div small {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.postbox-attachments > div small {
  color: var(--muted);
}

.postbox-access-explanation {
  align-items: flex-start;
  gap: 10px;
  border-left: 3px solid var(--green);
  background: var(--success-soft);
  padding: 10px 12px;
}

.postbox-access-explanation p {
  margin: 3px 0 0;
  color: var(--muted);
  line-height: 1.4;
}

.postbox-note {
  max-width: 470px;
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}

.postbox-dialog {
  width: min(720px, calc(100vw - 32px));
  max-width: none;
}

.postbox-template-dialog {
  width: min(900px, calc(100vw - 32px));
}

.postbox-form-grid input,
.postbox-form-grid select {
  width: 100%;
}

.postbox-toggle-field {
  min-height: 62px;
  display: flex;
  align-items: flex-end;
  padding-bottom: 7px;
}

.postbox-routing-section {
  grid-column: 1 / -1;
  display: grid;
  gap: 14px;
  border-top: var(--border-line);
  padding-top: 16px;
}

.postbox-routing-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}

.postbox-routing-heading > div:first-child {
  display: grid;
  gap: 3px;
}

.postbox-routing-heading span {
  color: var(--muted);
  font-size: 12px;
}

.postbox-relation-options {
  min-height: 38px;
  display: flex;
  flex-wrap: wrap;
  align-content: center;
  gap: 8px 14px;
}

.postbox-relation-options label {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--text-strong);
  font-size: 13px;
}

.postbox-relation-options input {
  width: auto;
}

.postbox-template-preview {
  display: grid;
  gap: 12px;
  border-top: var(--border-line);
  margin-top: 18px;
  padding-top: 16px;
}

.postbox-preview-targets {
  max-height: 280px;
  display: grid;
  gap: 1px;
  overflow: auto;
  background: var(--border-color);
  border: var(--border-line);
}

.postbox-preview-targets > div {
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background: var(--surface);
  padding: 10px 12px;
}

.postbox-preview-targets > div > div:first-child {
  min-width: 0;
  display: grid;
  gap: 2px;
}

.postbox-preview-targets span,
.postbox-preview-targets small {
  color: var(--muted);
  font-size: 12px;
}

.postbox-preview-targets code {
  overflow: hidden;
  color: var(--text-strong);
  text-overflow: ellipsis;
  white-space: nowrap;
}

.postbox-preview-status {
  flex: 0 0 auto;
  display: grid;
  justify-items: end;
  gap: 4px;
}

.postbox-form-note {
  margin: 15px 0 0;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.5;
}

.postbox-dialog-actions {
  width: 100%;
  display: flex;
  justify-content: space-between;
  gap: 12px;
}

.postbox-source-selector {
  max-height: 310px;
  display: grid;
  gap: 5px;
  overflow: auto;
  border: var(--border-line);
  margin: 16px 0 0;
  padding: 10px;
}

.postbox-source-selector legend {
  color: var(--muted);
  font-size: 12px;
  font-weight: 800;
}

.postbox-source-selector label {
  display: flex;
  align-items: center;
  gap: 9px;
  border-radius: var(--radius-sm);
  padding: 7px 8px;
}

.postbox-source-selector label:hover {
  background: var(--sidebar-hover-bg);
}

.postbox-source-selector label span {
  min-width: 0;
  display: grid;
  gap: 2px;
}

.postbox-source-selector small {
  color: var(--muted);
}

.postbox-message-dialog {
  width: min(720px, calc(100vw - 32px));
}

.postbox-compose-grid {
  grid-template-columns: minmax(0, 2fr) minmax(160px, 1fr);
}

.postbox-compose-wide {
  grid-column: 1 / -1;
}

.postbox-compose-grid textarea {
  width: 100%;
  min-height: 180px;
  resize: vertical;
}

.postbox-quick-detail {
  display: grid;
  gap: 7px;
  margin-top: 12px;
  border-top: var(--border-line);
  padding-top: 12px;
}

.postbox-quick-detail > span,
.postbox-quick-detail > p {
  margin: 0;
  color: var(--muted);
  font-size: 12px;
}

.postbox-quick-detail > p {
  display: -webkit-box;
  overflow: hidden;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 4;
}

.postbox-dialog-actions.end {
  justify-content: flex-end;
  gap: 8px;
}

.postbox-admin-page > .segmented-control {
  margin-bottom: 14px;
}

.postbox-admin-workspace {
  min-height: 520px;
  display: grid;
  grid-template-columns: minmax(250px, 320px) minmax(0, 1fr);
  border: var(--border-line);
  background: var(--panel);
  overflow: hidden;
}

.postbox-admin-list {
  min-width: 0;
  min-height: 0;
  max-height: 680px;
  overflow: auto;
  border-right: var(--border-line);
  background: var(--panel-soft);
  padding: 8px;
}

.postbox-admin-detail {
  min-width: 0;
  min-height: 0;
  max-height: 680px;
  overflow: auto;
  padding: 20px 24px 26px;
}

.postbox-admin-detail-heading {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  border-bottom: var(--border-line);
  padding-bottom: 17px;
  margin-bottom: 18px;
}

.postbox-admin-detail-heading h2 {
  margin: 2px 0 4px;
  color: var(--text-strong);
  font-size: 20px;
}

.postbox-admin-detail-heading p {
  margin: 0;
  color: var(--muted);
}

.postbox-detail-kicker {
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
}

.postbox-admin-properties {
  border-bottom: var(--border-line);
  padding-bottom: 18px;
}

.postbox-revision-history {
  margin-top: 18px;
}

.postbox-revision-history h3 {
  margin: 0 0 9px;
  color: var(--text-strong);
  font-size: 14px;
}

.postbox-revision-history > div {
  display: grid;
  grid-template-columns: minmax(120px, 1fr) minmax(160px, 2fr) auto;
  align-items: center;
  gap: 10px;
  border-top: var(--border-line);
  padding: 9px 0;
}

.postbox-revision-history > div span:not(.status-badge) {
  color: var(--muted);
}

@media (max-width: 1280px) {
  .postbox-shell {
    grid-template-columns: minmax(230px, 290px) minmax(280px, 340px) minmax(330px, 1fr);
    overflow-x: auto;
  }
}

@media (max-width: 900px) {
  .postbox-page {
    height: auto;
    min-height: calc(100vh - 115px);
    overflow: auto;
  }

  .postbox-shell {
    grid-template-columns: 1fr;
    height: auto;
    overflow: visible;
  }

  .postbox-directory,
  .postbox-message-list {
    min-height: 260px;
    max-height: 42vh;
    border-right: 0;
    border-bottom: var(--border-line);
  }

  .postbox-detail {
    min-height: 440px;
  }

  .postbox-admin-workspace {
    grid-template-columns: 1fr;
  }

  .postbox-admin-list {
    max-height: 260px;
    border-right: 0;
    border-bottom: var(--border-line);
  }

  .postbox-admin-detail-heading {
    flex-direction: column;
  }
}

@media (max-width: 680px) {
  .postbox-provenance dl,
  .postbox-admin-properties {
    grid-template-columns: 1fr;
  }

  .postbox-message-detail {
    padding: 16px;
  }

  .postbox-routing-heading {
    align-items: flex-start;
    flex-direction: column;
  }

}