/* ── Reset & Base ─────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --navy:       #1a3a5c;
  --navy-dark:  #122a44;
  --navy-light: #2a5a8c;
  --white:      #ffffff;
  --gray-50:    #f5f6f8;
  --gray-100:   #e9ecef;
  --gray-200:   #e2e6ea;
  --gray-400:   #adb5bd;
  --gray-600:   #6c757d;
  --gray-800:   #343a40;
  --green:      #2d8a4e;
  --green-bg:   #d4edda;
  --red:        #c0392b;
  --red-bg:     #fde8e6;
  --amber:      #d4840a;
  --amber-bg:   #fff3cd;
  --blue:       #3a7bd5;
  --blue-bg:    #dce8fb;
  --font:       'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  --radius:     10px;
  --shadow:     0 2px 8px rgba(0,0,0,0.08);
  --shadow-md:  0 4px 16px rgba(0,0,0,0.12);
  --transition: 0.15s ease;
}

html { font-size: 15px; }
body {
  font-family: var(--font);
  background: var(--gray-50);
  color: var(--gray-800);
  line-height: 1.5;
  min-height: 100vh;
}

a { color: var(--navy); text-decoration: none; }
a:hover { color: var(--navy-light); }

/* ── Topbar ───────────────────────────────────────────────────────────── */
.topbar {
  background: var(--navy);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  height: 56px;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}
.topbar-brand { display: flex; align-items: center; gap: 10px; color: var(--white); font-weight: 600; font-size: 1.05rem; }
.brand-icon { background: rgba(255,255,255,0.15); border-radius: 6px; padding: 4px 8px; font-weight: 700; font-size: 0.85rem; letter-spacing: 1px; }
.topbar-right { display: flex; align-items: center; gap: 16px; }
.topbar-link { color: rgba(255,255,255,0.8); font-size: 0.875rem; transition: color var(--transition); }
.topbar-link:hover { color: var(--white); }
.topbar-logout { color: rgba(255,255,255,0.6); }
.topbar-context { font-size: 0.8rem; color: rgba(255,255,255,0.6); }
.topbar-avatar {
  width: 34px; height: 34px; border-radius: 50%;
  background: var(--navy-light);
  color: var(--white);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.75rem; font-weight: 700;
  cursor: default;
}

/* ── Page wrapper ─────────────────────────────────────────────────────── */
.page-wrapper { max-width: 1400px; margin: 0 auto; padding: 24px 24px 40px; }

/* ── Buttons ──────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 8px 18px; border-radius: 7px; font-size: 0.875rem; font-weight: 500;
  cursor: pointer; border: none; text-decoration: none;
  transition: background var(--transition), transform var(--transition), opacity var(--transition);
  line-height: 1;
}
.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary   { background: var(--navy);  color: #fff; }
.btn-primary:hover  { background: var(--navy-dark); color: #fff; }
.btn-secondary { background: var(--gray-100); color: var(--gray-800); border: 1px solid var(--gray-200); }
.btn-secondary:hover { background: var(--gray-200); }
.btn-danger    { background: var(--red-bg); color: var(--red); border: 1px solid #f5c6cb; }
.btn-danger:hover { background: #f5c6cb; }
.btn-archive   { background: var(--gray-100); color: var(--gray-800); border: 1px solid var(--gray-200); }
.btn-archive:hover { background: var(--amber-bg); color: var(--amber); border-color: #ffe58f; }
.btn-warning   { background: #ede9fe; color: #6d28d9; border: 1px solid #c4b5fd; }
.btn-warning:hover { background: #ddd6fe; }
.btn-ghost     { background: transparent; color: var(--gray-600); border: 1px solid var(--gray-200); }
.btn-ghost:hover { background: var(--gray-100); }
.btn-block     { width: 100%; }
.btn-sm        { padding: 5px 12px; font-size: 0.8rem; }
.btn-xs        { padding: 3px 8px; font-size: 0.75rem; border-radius: 4px; }

/* ── Forms ────────────────────────────────────────────────────────────── */
.form-group { display: flex; flex-direction: column; gap: 5px; margin-bottom: 16px; }
.form-group label { font-size: 0.85rem; font-weight: 600; color: var(--gray-800); }
.form-control {
  height: 38px;
  padding: 0 12px;
  border: 1px solid #ced4da;
  border-radius: 7px;
  font-size: 0.9rem;
  font-family: var(--font);
  background: var(--white);
  color: var(--gray-800);
  transition: border-color var(--transition), box-shadow var(--transition);
  width: 100%;
}
.form-control:focus {
  outline: none;
  border-color: var(--navy-light);
  box-shadow: 0 0 0 3px rgba(26,58,92,0.15);
}
textarea.form-control { height: auto; padding: 10px 12px; }
select.form-control { padding-right: 28px; }
.form-hint { font-size: 0.78rem; color: var(--gray-600); }
.form-row { display: flex; gap: 16px; flex-wrap: wrap; }
.form-row .form-group { flex: 1; min-width: 160px; }
.form-row .flex-2 { flex: 2; }
.form-row .form-group-sm { flex: 0 0 110px; }
.form-actions { display: flex; gap: 10px; align-items: center; margin-top: 24px; }
.form-card { background: var(--white); border: 1px solid var(--gray-200); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow); }
.form-section { margin-bottom: 28px; }
.form-section h3 { font-size: 1rem; color: var(--navy); margin-bottom: 16px; padding-bottom: 8px; border-bottom: 1px solid var(--gray-200); }

/* ── Alerts ───────────────────────────────────────────────────────────── */
.alert { padding: 12px 16px; border-radius: 8px; margin-bottom: 16px; font-size: 0.875rem; }
.alert-success { background: var(--green-bg); color: var(--green); border: 1px solid #b8ddc4; }
.alert-error   { background: var(--red-bg);   color: var(--red);   border: 1px solid #f5c6cb; }
.alert-info    { background: var(--blue-bg);   color: var(--blue);  border: 1px solid #b8d4f5; }

/* ── Badges ───────────────────────────────────────────────────────────── */
.badge { display: inline-flex; align-items: center; padding: 2px 8px; border-radius: 999px; font-size: 0.75rem; font-weight: 600; }
.badge-green { background: var(--green-bg);  color: var(--green); }
.badge-red   { background: var(--red-bg);    color: var(--red); }
.badge-amber { background: var(--amber-bg);  color: var(--amber); }
.badge-blue  { background: var(--blue-bg);   color: var(--blue); }
.badge-gray  { background: var(--gray-100);  color: var(--gray-600); }
.badge-dr    { background: #ede9fe;          color: #6d28d9; font-weight: 700; }
[data-theme="dark"] .badge-dr { background: #2d1f4e; color: #c4b5fd; }

/* Dropped row */
.dr-row { opacity: 0.55; }
.dr-row:hover { opacity: 0.75; }

/* Stat card for dropped count */
.stat-dr { border-top: 3px solid #7c3aed !important; }
.stat-dr .stat-value { color: #7c3aed; }

/* Dropped notice banner (student portal cards) */
.dropped-notice {
  background: #ede9fe; color: #5b21b6; font-size: 0.78rem; font-weight: 600;
  padding: 6px 10px; border-radius: 5px; margin-bottom: 8px;
  display: flex; align-items: center; gap: 6px;
}
[data-theme="dark"] .dropped-notice { background: #2d1f4e; color: #c4b5fd; }

/* Dropped subject card */
.subject-card-dropped { border-color: #c4b5fd !important; background: #faf5ff !important; opacity: 0.88; }
[data-theme="dark"] .subject-card-dropped { background: #1e1a2e !important; border-color: #6d28d9 !important; }

/* Dropped alert banner (student grades page) */
.alert-dr {
  background: #ede9fe; border-left: 4px solid #7c3aed; color: #4c1d95;
  padding: 12px 16px; border-radius: var(--radius);
  display: flex; align-items: flex-start; gap: 8px; font-size: 0.88rem;
}
[data-theme="dark"] .alert-dr { background: #2d1f4e; color: #ddd6fe; border-color: #7c3aed; }

/* ── Tables ───────────────────────────────────────────────────────────── */
.data-table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }
.data-table th { background: var(--navy); color: var(--white); padding: 10px 12px; text-align: left; font-weight: 600; font-size: 0.82rem; white-space: nowrap; }
.data-table td { padding: 9px 12px; border-bottom: 1px solid var(--gray-100); }
.data-table tbody tr:hover td { background: #f0f4fa; }
.data-table tbody tr:nth-child(even) td { background: #fafbfd; }
.table-wrapper  { overflow-x: auto; border-radius: var(--radius); border: 1px solid var(--gray-200); box-shadow: var(--shadow); }
.table-responsive { overflow-x: auto; border-radius: var(--radius); border: 1px solid var(--gray-200); box-shadow: var(--shadow); }

/* ── Stats strip ─────────────────────────────────────────────────────── */
.stats-strip { display: flex; gap: 16px; margin-bottom: 24px; flex-wrap: wrap; }
.stat-card { background: var(--white); border: 1px solid var(--gray-200); border-radius: var(--radius); padding: 16px 22px; box-shadow: var(--shadow); flex: 1; min-width: 130px; }
.stat-value { font-size: 1.8rem; font-weight: 700; color: var(--navy); line-height: 1.1; }
.stat-label { font-size: 0.8rem; color: var(--gray-600); margin-top: 4px; }
.stat-pass .stat-value { color: var(--green); }
.stat-fail .stat-value { color: var(--red); }
.stat-inc  .stat-value { color: var(--amber); }
.stats-strip-sm .stat-card { padding: 12px 16px; }
.stats-strip-sm .stat-value { font-size: 1.4rem; }

/* ── Modal ────────────────────────────────────────────────────────────── */
.modal { position: fixed; inset: 0; z-index: 500; display: flex; align-items: center; justify-content: center; }
.modal.hidden { display: none; }
.modal-overlay { position: absolute; inset: 0; background: rgba(0,0,0,0.45); }
.modal-box { position: relative; background: var(--white); border-radius: var(--radius); min-width: 360px; max-width: 500px; width: 90%; box-shadow: var(--shadow-md); overflow: hidden; }
.modal-box h3 { margin-bottom: 20px; color: var(--navy); }
.modal-header { display: flex; align-items: center; justify-content: space-between; padding: 18px 22px; border-bottom: 1px solid var(--gray-200); }
.modal-title  { font-size: 1rem; font-weight: 700; color: var(--navy); margin: 0; }
.modal-close  { background: none; border: none; font-size: 1.4rem; line-height: 1; cursor: pointer; color: var(--gray-500); padding: 0 4px; }
.modal-close:hover { color: var(--gray-800); }
.modal-body   { padding: 20px 22px; }
.modal-footer { padding: 14px 22px; border-top: 1px solid var(--gray-200); display: flex; justify-content: flex-end; gap: 10px; }

/* ── Page header ─────────────────────────────────────────────────────── */
.page-header { margin-bottom: 20px; }
.page-header h2 { font-size: 1.4rem; color: var(--navy); margin-top: 6px; }
.back-link { font-size: 0.85rem; color: var(--gray-600); }
.back-link:hover { color: var(--navy); }

/* ── Footer ───────────────────────────────────────────────────────────── */
.site-footer { text-align: center; padding: 20px; font-size: 0.8rem; color: var(--gray-400); border-top: 1px solid var(--gray-200); margin-top: 40px; }

/* ── Auth page ────────────────────────────────────────────────────────── */
.auth-page { display: flex; align-items: center; justify-content: center; min-height: 100vh; background: linear-gradient(135deg, var(--navy) 0%, var(--navy-light) 100%); }
.auth-container { width: 100%; max-width: 420px; padding: 20px; }
.auth-card { background: var(--white); border-radius: 14px; padding: 36px; box-shadow: var(--shadow-md); }
.auth-logo { text-align: center; margin-bottom: 28px; }
.logo-icon { background: var(--navy); color: var(--white); width: 56px; height: 56px; border-radius: 12px; font-size: 1rem; font-weight: 700; display: inline-flex; align-items: center; justify-content: center; margin-bottom: 12px; }
.auth-logo h1 { font-size: 1.2rem; color: var(--navy); }
.auth-logo p { font-size: 0.85rem; color: var(--gray-600); margin-top: 4px; }
.auth-footer { text-align: center; margin-top: 20px; font-size: 0.85rem; color: var(--gray-600); }

/* ── Alert banner ─────────────────────────────────────────────────────── */
.alert-banner { border-radius: 8px; padding: 12px 16px; margin-bottom: 16px; font-size: 0.875rem; }
.alert-amber { background: var(--amber-bg); color: var(--amber); border: 1px solid #ffe083; }
.alert-finalized { background: #eff6ff; color: #1e40af; border: 1px solid #bfdbfe; }
.alert-info      { background: #eff6ff; color: #1e40af; border: 1px solid #bfdbfe; border-radius: var(--radius); padding: 10px 14px; }
[data-theme="dark"] .alert-finalized { background: #1e2a4a; color: #93c5fd; border-color: #1e40af; }
[data-theme="dark"] .alert-info      { background: #1e2a4a; color: #93c5fd; border-color: #1e40af; }

/* Finalize section in settings */
.finalize-section { background: var(--white); border: 1px solid var(--gray-200); border-radius: var(--radius); padding: 18px 20px; margin-bottom: 20px; box-shadow: var(--shadow); }
.finalize-section h4 { margin: 0 0 10px; font-size: 0.95rem; color: var(--navy); }
.alert-banner ul { margin: 8px 0 0 18px; }
.alert-banner li { margin: 4px 0; }
.banner-toggle { background: none; border: none; color: var(--amber); font-weight: 600; cursor: pointer; font-size: 0.875rem; padding: 0; }
.hidden { display: none !important; }

/* ── Save status ─────────────────────────────────────────────────────── */
.save-status { font-size: 0.8rem; color: var(--gray-600); transition: opacity var(--transition); }
.save-status.saving { color: var(--blue); }
.save-status.saved  { color: var(--green); }
.save-status.error  { color: var(--red); }

/* ── Info table ──────────────────────────────────────────────────────── */
.info-table { width: 100%; border-collapse: collapse; }
.info-table th { text-align: left; padding: 8px 12px; background: var(--gray-50); border: 1px solid var(--gray-200); font-weight: 600; width: 260px; color: var(--gray-600); font-size: 0.85rem; }
.info-table td { padding: 8px 12px; border: 1px solid var(--gray-200); font-size: 0.9rem; }

/* ── Empty state ─────────────────────────────────────────────────────── */
.empty-state { text-align: center; padding: 48px 24px; color: var(--gray-600); }
.empty-icon { font-size: 3rem; margin-bottom: 12px; }
.empty-state h3 { color: var(--navy); margin-bottom: 8px; }
.empty-state p { margin-bottom: 16px; }

/* ── Utilities ───────────────────────────────────────────────────────── */
.text-muted { color: var(--gray-600); font-size: 0.875rem; }
.risk-badge { font-size: 0.75rem; color: var(--amber); background: var(--amber-bg); border-radius: 999px; padding: 2px 8px; white-space: nowrap; }
.risk-flag { color: var(--amber); margin-left: 4px; }

/* ── Theme toggle button ─────────────────────────────────────────────── */
.theme-toggle {
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 20px;
  color: rgba(255,255,255,0.9);
  cursor: pointer;
  font-size: 1rem;
  width: 34px; height: 34px;
  display: flex; align-items: center; justify-content: center;
  transition: background var(--transition), transform var(--transition);
  padding: 0;
}
.theme-toggle:hover { background: rgba(255,255,255,0.22); transform: scale(1.1); }
.theme-toggle .icon-sun  { display: inline; }
.theme-toggle .icon-moon { display: none; }
[data-theme="dark"] .theme-toggle .icon-sun  { display: none; }
[data-theme="dark"] .theme-toggle .icon-moon { display: inline; }

/* ── Dark mode ───────────────────────────────────────────────────────── */
[data-theme="dark"] {
  --navy:       #7eb4ea;
  --navy-dark:  #5a9ade;
  --navy-light: #a0ccf5;
  --white:      #1c1f2e;
  --gray-50:    #12141f;
  --gray-100:   #232535;
  --gray-200:   #333550;
  --gray-400:   #636580;
  --gray-600:   #9496b4;
  --gray-800:   #dde0f0;
  --green:      #4ade80;
  --green-bg:   #0a2016;
  --red:        #f87171;
  --red-bg:     #2c0c0c;
  --amber:      #fbbf24;
  --amber-bg:   #261600;
  --blue:       #60a5fa;
  --blue-bg:    #0b1d35;
  --shadow:     0 2px 8px rgba(0,0,0,0.5);
  --shadow-md:  0 4px 20px rgba(0,0,0,0.7);
}

/* Topbar & nav stay dark-navy regardless */
[data-theme="dark"] .topbar { background: #101728; box-shadow: 0 2px 8px rgba(0,0,0,0.6); }
[data-theme="dark"] .topbar-avatar { background: #2a4a6e; }

/* Primary button uses a fixed dark-blue tint so it stays readable */
[data-theme="dark"] .btn-primary { background: #1e3a5e; color: #d0e4f8; }
[data-theme="dark"] .btn-primary:hover { background: #152c4a; }

/* Tables */
[data-theme="dark"] .data-table th { background: #1a2540; color: #c8d8ec; }
[data-theme="dark"] .data-table tbody tr:hover td { background: var(--gray-100); }
[data-theme="dark"] .data-table tbody tr:nth-child(even) td { background: #1e2030; }

/* Form inputs */
[data-theme="dark"] .form-control { border-color: var(--gray-200); }
[data-theme="dark"] .form-control:focus { box-shadow: 0 0 0 3px rgba(126,180,234,0.2); border-color: var(--navy); }
[data-theme="dark"] select.form-control option { background: var(--white); }

/* Auth page */
[data-theme="dark"] .auth-page { background: linear-gradient(135deg, #0a1520 0%, #101f35 100%); }

/* Grading score input */
[data-theme="dark"] .score-input { color: var(--gray-800); }
[data-theme="dark"] .score-input:focus { background: #2a2d40; outline-color: var(--navy); }

/* ── Mobile / Responsive ─────────────────────────────────────────────── */
@media (max-width: 768px) {
  /* Topbar collapses to stacked layout */
  .topbar { flex-wrap: wrap; gap: 6px; padding: 8px 12px; }
  .topbar-right { flex-wrap: wrap; gap: 6px; }
  .topbar-context { display: none; }
  .brand-text { font-size: 0.85rem; }

  /* Page wrapper */
  .page-wrapper { padding: 12px; }

  /* Stats strip: 2 per row on mobile */
  .stats-strip { grid-template-columns: repeat(2, 1fr); gap: 8px; }
  .stat-card { padding: 12px; }
  .stat-value { font-size: 1.5rem; }

  /* Form rows go single column */
  .form-row { flex-direction: column; }

  /* Tables: horizontal scroll */
  .table-wrapper, .table-responsive { overflow-x: auto; -webkit-overflow-scrolling: touch; }

  /* Buttons */
  .btn-block { width: 100%; }

  /* Auth card */
  .auth-container { padding: 12px; }
  .auth-card { padding: 24px 18px; }

  /* Tab nav: horizontal scroll */
  .tab-nav { overflow-x: auto; white-space: nowrap; -webkit-overflow-scrolling: touch; }
  .tab-link { padding: 8px 12px; font-size: 0.82rem; }

  /* Settings actions: stack vertically */
  .settings-actions { flex-direction: column; align-items: stretch; }
  .settings-actions .btn { text-align: center; }

  /* Subject cards: single column */
  .student-subjects-grid { grid-template-columns: 1fr; }

  /* Header actions: stack */
  .cr-header { flex-direction: column; gap: 10px; }
  .cr-header-actions { display: flex; flex-wrap: wrap; gap: 6px; }

  /* Export grid: single column */
  .export-grid { grid-template-columns: 1fr; }

  /* Modal box */
  .modal-box { margin: 12px; width: calc(100% - 24px); max-height: 90vh; overflow-y: auto; }

  /* Signature section in PDF prep (not PDF itself) */
  .sig-section { flex-direction: column; gap: 20px; }
}

@media (max-width: 480px) {
  .stats-strip { grid-template-columns: 1fr 1fr; }
  .topbar-link:not(.topbar-logout) { display: none; }
  .brand-icon { width: 28px; height: 28px; font-size: 0.7rem; }
  .page-header h2 { font-size: 1.1rem; }
}