/* ── Teacher Portal Layout (supplements shared.css) ───────────────── */
  .shell { max-width: 1200px; margin: 0 auto; padding: 24px; }
  .hidden { display: none !important; }
  .login { min-height: 100vh; display: grid; place-items: center; padding: 24px; }
  .login-card, .panel { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius-lg); box-shadow: var(--shadow-lg); }
  .login-card { width: 100%; max-width: 420px; padding: 28px; }
  .eyebrow { text-transform: uppercase; letter-spacing: 0.18em; color: var(--warning); font-size: 11px; margin-bottom: 10px; }
  .login-card p { color: var(--text-muted); margin: 10px 0 20px; line-height: 1.5; }
  label { display: block; margin: 14px 0 6px; font-size: 12px; text-transform: uppercase; letter-spacing: 0.08em; color: var(--text-muted); }
  .error { color: var(--danger); margin-top: 12px; }
  .btn-secondary { background: var(--bg-alt); color: var(--text); border: 1px solid var(--border); }
  .topbar { display: flex; justify-content: space-between; align-items: center; gap: 16px; margin-bottom: 22px; }
  .title-block p { margin: 6px 0 0; color: var(--text-muted); }
  .hero { display: grid; grid-template-columns: 1.4fr 1fr; gap: 16px; margin-bottom: 18px; }
  .panel { padding: 20px; }
  .stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 18px; }
  .stat { border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 14px; background: var(--card); }
  .stat strong { display: block; font-size: 28px; margin-top: 6px; }
  .layout { display: grid; grid-template-columns: 320px 1fr; gap: 16px; }
  .class-card { border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 14px; background: var(--card); margin-bottom: 10px; cursor: pointer; transition: transform 0.15s ease, border-color 0.15s ease; }
  .class-card:hover, .class-card.active { transform: translateY(-1px); border-color: var(--primary); }
  .class-card .meta { color: var(--text-muted); font-size: 13px; margin-top: 4px; }
  .section-nav { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 14px; }
  .section-tab { background: var(--bg-alt); color: var(--text); border: 1px solid var(--border); border-radius: var(--radius-md); padding: 8px 14px; font-size: 13px; font-weight: 500; font-family: inherit; cursor: pointer; }
  .section-tab:hover { background: var(--card-hover); }
  .section-tab.active { background: var(--primary); color: white; border-color: var(--primary); }
  .list th, .list td { border-bottom-color: var(--border-light); }
  .list th { color: var(--text-muted); }
  .subtle { color: var(--text-muted); }
  .toolbar { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-bottom: 12px; }
  .toolbar-actions { display: flex; gap: 10px; align-items: center; }
  .pill { display: inline-flex; align-items: center; gap: 6px; background: var(--primary-light); color: var(--primary); border-radius: 999px; padding: 4px 10px; font-size: 12px; }
  .section { margin-top: 16px; }
  .section h3 { margin-bottom: 8px; }
  .section-panel { display: none; }
  .section-panel.active { display: block; }
  .attendance-notes { width: 100%; }
  .attendance-toolbar { display: flex; gap: 10px; align-items: center; margin-bottom: 12px; flex-wrap: wrap; }
  .attendance-check { width: 20px; height: 20px; accent-color: var(--danger); }
  .attendance-status-cell { text-align: center; }
  .attendance-hint { margin: 0 0 10px; font-size: 13px; }
  .student-name { display: inline-block; padding: 6px 0; line-height: 1.7; }
  .toolbar-search { min-width: 220px; }
  .timetable-grid { display: grid; grid-template-columns: 110px repeat(6, 1fr); gap: 8px; }
  .timetable-head, .timetable-cell { border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 10px; background: var(--card); min-height: 82px; }
  .timetable-head { font-size: 12px; text-transform: uppercase; letter-spacing: 0.08em; color: var(--text-muted); font-weight: 700; min-height: auto; }
  .period-label { font-size: 12px; color: var(--text-muted); }
  .period-label strong { display: block; color: var(--text); font-size: 14px; margin-bottom: 4px; }
  .lesson { font-size: 13px; line-height: 1.45; }
  .lesson strong { display: block; color: var(--primary); }
  .modal-backdrop { position: fixed; inset: 0; background: rgba(15, 23, 42, 0.45); display: none; align-items: center; justify-content: center; padding: 24px; overflow-y: auto; z-index: 100; }
  .modal-backdrop.open { display: flex; }
  .modal-card { width: 100%; max-width: 560px; max-height: calc(100vh - 48px); overflow-y: auto; background: var(--card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 22px; box-shadow: var(--shadow-lg); }
  .modal-actions { display: flex; gap: 10px; justify-content: flex-end; margin-top: 16px; flex-wrap: wrap; }
  .summary-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; margin-top: 12px; }
  .summary-tile { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 12px; text-align: center; }
  .summary-tile strong { display: block; font-size: 24px; }
  @media (max-width: 900px) {
    .hero, .layout, .stats { grid-template-columns: 1fr; }
    .summary-grid { grid-template-columns: repeat(2, 1fr); }
    .attendance-check { width: 36px; height: 36px; }
    .list { display: block; overflow-x: auto; -webkit-overflow-scrolling: touch; }
    .timetable-grid { overflow-x: auto; }
  }