.admin-body {
  --admin-ink: #263248;
  --admin-navy: #385577;
  --admin-paper: #fffdfb;
  --admin-soft: #edf5f8;
  --admin-warning: #a64b38;
}

[hidden] { display: none !important; }

.admin-topbar { border-bottom-color: var(--line2); }
.admin-brand { text-decoration: none; }
.admin-brand span {
  margin-left: 8px; padding-left: 10px; border-left: 1px solid var(--line);
  color: var(--admin-navy); font-size: 14px; letter-spacing: .08em;
}
.admin-shell { max-width: 1240px; margin: 0 auto; }
.admin-gate { max-width: 620px; margin: 7vh auto 0; text-align: center; }
.admin-gate .card { padding: 38px 30px; }
.admin-gate h1, .admin-heading h1 { margin: 4px 0 8px; color: var(--admin-ink); }
.gate-mark, .eyebrow {
  margin: 0; color: var(--sky-ink); font: 800 11px/1.2 "SFMono-Regular", Menlo, Consolas, monospace;
  letter-spacing: .18em;
}
.gate-mark { display: inline-block; padding: 5px 9px; background: var(--admin-soft); border-radius: 6px; }
.gate-mark.denied, .eyebrow.warning { color: var(--admin-warning); background: #fff0eb; }
.denied-card { border-color: #ecc7bb; }

.admin-heading {
  display: flex; align-items: flex-start; justify-content: space-between; gap: 20px;
  margin: 4px 0 18px;
}
.admin-heading .hint { margin-bottom: 0; }
.admin-tabs { display: flex; gap: 4px; border-bottom: 1px solid var(--line); margin-bottom: 22px; }
.admin-tab {
  border-radius: 9px 9px 0 0; background: transparent; color: var(--muted);
  padding: 11px 18px; border-bottom: 3px solid transparent;
}
.admin-tab.active { color: var(--admin-navy); border-bottom-color: var(--sky-ink); background: #fff; }

.class-search {
  display: grid; grid-template-columns: 100px minmax(0, 520px); align-items: end; gap: 14px;
  padding: 18px; background: var(--admin-paper); border: 1px solid var(--line2); border-radius: 14px;
}
.class-search label { font-weight: 700; color: var(--admin-ink); }
.class-search select { margin: 0; min-width: 0; }
.admin-message { min-height: 22px; margin: 10px 2px; color: var(--muted); font-size: 14px; }
.admin-message.error { color: var(--err); }

.section-heading {
  display: flex; align-items: end; justify-content: space-between; gap: 16px; margin: 26px 0 10px;
}
.section-heading.compact { margin-top: 0; }
.section-heading h2 { margin: 3px 0 0; font-size: 22px; }
.count-chip {
  border: 1px solid var(--line2); background: var(--admin-soft); color: var(--admin-navy);
  padding: 5px 10px; border-radius: 999px; font-size: 13px; font-weight: 700;
}
.count-chip.warning { color: var(--admin-warning); background: #fff0eb; border-color: #ecc7bb; }

.table-wrap { width: 100%; overflow-x: auto; border: 1px solid var(--line); border-radius: 12px; background: #fff; }
.admin-table { width: 100%; border-collapse: collapse; min-width: 920px; }
.admin-table th, .admin-table td { padding: 11px 12px; text-align: left; border-bottom: 1px solid #edf0f4; vertical-align: middle; }
.admin-table th {
  position: sticky; top: 0; background: #f8fafb; color: var(--muted);
  font-size: 12px; letter-spacing: .035em; white-space: nowrap;
}
.admin-table tbody tr:last-child td { border-bottom: 0; }
.admin-table tbody tr:hover { background: #fbf7fa; }
.admin-table button { padding: 7px 10px; font-size: 13px; white-space: nowrap; }
.seat-index {
  display: inline-grid; place-items: center; width: 34px; height: 34px; border-radius: 8px;
  background: var(--admin-ink); color: white; font: 800 14px/1 "SFMono-Regular", Menlo, monospace;
}
.student-email { max-width: 220px; overflow-wrap: anywhere; }
.status-chip { display: inline-block; padding: 4px 8px; border-radius: 999px; font-size: 12px; font-weight: 700; }
.status-chip.enabled { background: #e1f3e6; color: var(--ok); }
.status-chip.disabled { background: #fceaea; color: var(--err); }

.detail-panel {
  margin-top: 18px; padding: 22px; border: 1px solid var(--line2); border-radius: 14px;
  background: linear-gradient(145deg, #fff 0%, #f7fbfc 100%);
}
.detail-head { display: flex; justify-content: space-between; align-items: start; gap: 12px; }
.detail-head h2 { margin-bottom: 2px; }
.detail-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; margin: 16px 0 20px; }
.data-card { background: #fff; border: 1px solid #e5ebef; border-radius: 10px; padding: 12px; min-width: 0; }
.data-card dt { color: var(--muted); font-size: 11px; letter-spacing: .04em; }
.data-card dd { margin: 4px 0 0; color: var(--admin-ink); font-weight: 700; overflow-wrap: anywhere; }
.data-card.wide { grid-column: 1 / -1; }
.json-value { margin: 6px 0 0; white-space: pre-wrap; word-break: break-word; font: 12px/1.55 "SFMono-Regular", Menlo, monospace; }
.detail-columns { display: grid; grid-template-columns: minmax(0, 1fr) minmax(320px, .72fr); gap: 18px; }
.detail-section { min-width: 0; }
.detail-section h3 { margin-top: 0; }
.detail-actions { padding: 16px; border: 1px solid var(--line); border-radius: 12px; background: #fff; }
.action-group + .action-group { border-top: 1px solid var(--line); margin-top: 16px; padding-top: 16px; }
.action-group h4 { margin: 0 0 10px; color: var(--admin-ink); }
.edit-row { display: grid; grid-template-columns: 100px minmax(0, 1fr) auto; gap: 8px; align-items: center; margin: 8px 0; }
.edit-row label { color: var(--muted); font-size: 13px; }
.edit-row input { margin: 0; padding: 9px 10px; font-size: 14px; }
.edit-row button { padding: 9px 11px; }
.danger-button { background: #fff; color: var(--err); border: 1px solid #e8b9b9; }
.danger-button:hover { background: #fff3f3; }
.history-table { min-width: 760px; }
.history-table .suspicious-row { background: #fff8f1; }
.spark-wrap { border: 1px solid #e7edf0; border-radius: 10px; background: #fff; padding: 8px; margin-bottom: 14px; }
.admin-spark { display: block; width: 100%; height: auto; }
.admin-spark-grid { stroke: #e7edf0; stroke-width: 1; }
.admin-spark-line { fill: none; stroke: var(--sky-ink); stroke-width: 2.5; stroke-linejoin: round; stroke-linecap: round; }
.admin-spark-dot { fill: var(--accent-ink); }
.admin-spark-label { fill: var(--muted); font: 10px sans-serif; }

.suspicious-panel { margin: 24px 0 8px; padding: 18px; border: 1px solid #ecc7bb; border-radius: 14px; background: #fffaf7; }
.suspicious-item {
  display: grid; grid-template-columns: 110px minmax(160px, .8fr) 1.3fr 1fr; gap: 10px;
  padding: 10px 0; border-top: 1px solid #f0d9cf; font-size: 13px;
}
.suspicious-item strong { color: var(--admin-warning); }
.empty-state { color: var(--muted); padding: 18px; text-align: center; }
.audit-table { min-width: 1050px; }
.audit-change { max-width: 420px; white-space: pre-wrap; word-break: break-word; font: 11px/1.45 "SFMono-Regular", Menlo, monospace; }

.admin-toast {
  position: fixed; right: 20px; bottom: 20px; max-width: min(420px, calc(100vw - 40px));
  padding: 12px 16px; border-radius: 10px; color: #fff; background: var(--admin-ink);
  box-shadow: var(--shadow); opacity: 0; transform: translateY(8px); pointer-events: none; transition: .18s;
}
.admin-toast.show { opacity: 1; transform: translateY(0); }
.admin-toast.error { background: var(--err); }

@media (max-width: 860px) {
  .detail-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .detail-columns { grid-template-columns: 1fr; }
  .suspicious-item { grid-template-columns: 90px 1fr; }
}

@media (max-width: 600px) {
  .admin-shell { padding: 16px 10px 48px; }
  .admin-brand span { display: none; }
  .class-search { grid-template-columns: 1fr; }
  .admin-heading { align-items: stretch; flex-direction: column; }
  .admin-heading button { align-self: flex-start; }
  .detail-grid { grid-template-columns: 1fr; }
  .edit-row { grid-template-columns: 1fr; }
  .suspicious-item { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  .admin-toast { transition: none; }
}

/* --- 姓名（2026-09-07）------------------------------------------------- */
.nick-chip,
.lock-chip {
  display: inline-block;
  margin-left: 4px;
  padding: 0 6px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 700;
  white-space: nowrap;
}

.nick-chip {
  background: var(--primary-soft);
  color: var(--primary-deep);
}

.lock-chip {
  background: var(--amber-soft);
  color: var(--amber-ink);
}