/* ==========================================================================
   STUDENT PORTAL SYSTEM — DESIGN SYSTEM
   ========================================================================== */

/* ---- CSS Custom Properties (Design Tokens) ---- */
:root {
  /* Brand Colors */
  --color-primary: #4f46e5;
  --color-primary-hover: #4338ca;
  --color-primary-light: #eef2ff;
  --color-primary-lighter: #c7d2fe;
  --color-primary-dark: #312e81;

  --color-success: #059669;
  --color-success-hover: #047857;
  --color-success-light: #dcfce7;
  --color-success-lighter: #bbf7d0;

  --color-warning: #d97706;
  --color-warning-hover: #b45309;
  --color-warning-light: #fef3c7;
  --color-warning-lighter: #fde68a;

  --color-danger: #dc2626;
  --color-danger-hover: #b91c1c;
  --color-danger-light: #fef2f2;
  --color-danger-lighter: #fecaca;

  --color-info: #0891b2;
  --color-info-light: #cffafe;

  /* Neutral Colors */
  --color-white: #ffffff;
  --color-50: #f8fafc;
  --color-100: #f1f5f9;
  --color-200: #e2e8f0;
  --color-300: #cbd5e1;
  --color-400: #94a3b8;
  --color-500: #64748b;
  --color-600: #475569;
  --color-700: #334155;
  --color-800: #1e293b;
  --color-900: #0f172a;
  --color-950: #020617;

  /* Semantic Colors */
  --bg-primary: var(--color-50);
  --bg-secondary: var(--color-white);
  --bg-tertiary: var(--color-100);
  --bg-inverse: var(--color-900);

  --text-primary: var(--color-900);
  --text-secondary: var(--color-600);
  --text-muted: var(--color-500);
  --text-inverse: var(--color-white);

  --border-light: var(--color-200);
  --border-medium: var(--color-300);
  --border-focus: var(--color-primary);

  /* Shadows */
  --shadow-xs: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-sm: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

  /* Border Radius */
  --radius-xs: 4px;
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* Spacing Scale */
  --space-1: 0.25rem;  /* 4px */
  --space-2: 0.5rem;   /* 8px */
  --space-3: 0.75rem;  /* 12px */
  --space-4: 1rem;     /* 16px */
  --space-5: 1.25rem;  /* 20px */
  --space-6: 1.5rem;   /* 24px */
  --space-8: 2rem;     /* 32px */
  --space-10: 2.5rem;  /* 40px */
  --space-12: 3rem;    /* 48px */
  --space-16: 4rem;    /* 64px */

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --text-xs: 0.7rem;     /* 11.2px */
  --text-sm: 0.8125rem;  /* 13px */
  --text-base: 0.9375rem; /* 15px */
  --text-lg: 1.0625rem;  /* 17px */
  --text-xl: 1.25rem;    /* 20px */
  --text-2xl: 1.5rem;    /* 24px */
  --text-3xl: 1.875rem;  /* 30px */
  --text-4xl: 2.25rem;   /* 36px */

  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;
  --font-extrabold: 800;

  --leading-tight: 1.25;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;

  /* Transitions */
  --transition-fast: 100ms ease;
  --transition-base: 150ms ease;
  --transition-slow: 250ms ease;

  /* Layout */
  --sidebar-width: 260px;
  --header-height: 64px;
  --container-max: 1200px;
  --content-max: 800px;

  /* Z-index */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal-backdrop: 400;
  --z-modal: 500;
  --z-toast: 600;
}

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

html { font-size: 16px; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: var(--leading-normal);
  min-height: 100vh;
}

a { color: var(--color-primary); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: var(--color-primary-hover); text-decoration: underline; }

button { font-family: inherit; cursor: pointer; }

input, select, textarea {
  font-family: inherit;
  font-size: var(--text-base);
  color: var(--text-primary);
  background: var(--bg-secondary);
  border: 1.5px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 0.7rem 0.9rem;
  width: 100%;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast), background var(--transition-fast);
}

input::placeholder, textarea::placeholder { color: var(--color-400); }

input:hover, select:hover, textarea:hover { border-color: var(--color-300); }

input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--color-primary-light);
  background: var(--bg-secondary);
}

label { display: block; font-size: var(--text-sm); font-weight: var(--font-semibold); color: var(--text-secondary); margin-bottom: var(--space-2); text-transform: uppercase; letter-spacing: 0.04em; }

/* ---- Layout Components ---- */

/* Container */
.container { width: 100%; max-width: var(--container-max); margin: 0 auto; padding: 0 var(--space-6); }
.container-narrow { max-width: var(--content-max); }

/* Grid */
.grid { display: grid; gap: var(--space-4); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } }

/* Flex utilities */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.flex-1 { flex: 1; }
.flex-wrap { flex-wrap: wrap; }

/* ---- Card ---- */
.card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.card-header {
  padding: var(--space-4) var(--space-6);
  border-bottom: 1px solid var(--border-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-3);
}
.card-header h3 { font-size: var(--text-lg); font-weight: var(--font-semibold); color: var(--text-primary); margin: 0; }
.card-header .meta { font-size: var(--text-xs); color: var(--text-muted); }
.card-body { padding: var(--space-6); }
.card-footer {
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--border-light);
  background: var(--bg-tertiary);
  display: flex;
  justify-content: flex-end;
  gap: var(--space-3);
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.625rem 1.125rem;
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  transition: all var(--transition-fast);
  white-space: nowrap;
}
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; }
.btn:active:not(:disabled) { transform: scale(0.98); }

.btn-sm { padding: 0.375rem 0.75rem; font-size: var(--text-xs); }
.btn-lg { padding: 0.875rem 1.5rem; font-size: var(--text-base); }

.btn-primary {
  background: var(--color-primary);
  color: var(--color-white);
  border-color: var(--color-primary);
}
.btn-primary:hover:not(:disabled) { background: var(--color-primary-hover); border-color: var(--color-primary-hover); }

.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--border-medium);
}
.btn-secondary:hover:not(:disabled) { background: var(--color-200); border-color: var(--color-300); }

.btn-danger {
  background: var(--color-danger);
  color: var(--color-white);
  border-color: var(--color-danger);
}
.btn-danger:hover:not(:disabled) { background: var(--color-danger-hover); border-color: var(--color-danger-hover); }

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border-color: transparent;
}
.btn-ghost:hover:not(:disabled) { background: var(--bg-tertiary); color: var(--text-primary); }

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}
.btn-outline:hover:not(:disabled) { background: var(--color-primary-light); }

.btn-success {
  background: var(--color-success);
  color: var(--color-white);
  border-color: var(--color-success);
}

.btn-warning {
  background: var(--color-warning);
  color: var(--color-white);
  border-color: var(--color-warning);
}
.btn-warning:hover:not(:disabled) { background: var(--color-warning-hover); border-color: var(--color-warning-hover); }
.btn-success:hover:not(:disabled) { background: var(--color-success-hover); border-color: var(--color-success-hover); }

.btn-icon { padding: 0.5rem; }
.btn-icon svg { width: 18px; height: 18px; }

/* ---- Form Elements ---- */
.form-group { margin-bottom: var(--space-4); }
.form-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: var(--space-4); }
.form-hint { font-size: var(--text-xs); color: var(--text-muted); margin-top: var(--space-1); }

.input-group { position: relative; }
.input-group input { padding-left: 2.5rem; }
.input-group .icon { position: absolute; left: 0.75rem; top: 50%; transform: translateY(-50%); width: 18px; height: 18px; color: var(--color-400); pointer-events: none; }

.select-wrapper { position: relative; }
.select-wrapper select { appearance: none; padding-right: 2.5rem; }
.select-wrapper::after {
  content: '';
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  width: 0; height: 0;
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-top: 6px solid var(--color-400);
  pointer-events: none;
}

.checkbox-group, .radio-group { display: flex; flex-direction: column; gap: var(--space-2); }
.checkbox-item, .radio-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3);
  background: var(--bg-tertiary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}
.checkbox-item:hover, .radio-item:hover { border-color: var(--color-primary); background: var(--color-primary-light); }
.checkbox-item input, .radio-item input { margin-top: 0.125rem; accent-color: var(--color-primary); width: 16px; height: 16px; flex-shrink: 0; }
.checkbox-item label, .radio-item label { margin: 0; font-size: var(--text-sm); font-weight: var(--font-normal); text-transform: none; letter-spacing: 0; cursor: pointer; flex: 1; }
.checkbox-item small, .radio-item small { color: var(--text-muted); font-size: var(--text-xs); display: block; margin-top: var(--space-1); }

/* ---- Badges ---- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.125rem 0.5rem;
  font-size: var(--text-xs);
  font-weight: var(--font-semibold);
  border-radius: var(--radius-full);
  white-space: nowrap;
}
  .badge-primary { background: var(--color-primary); color: var(--color-white); }
  .badge-success { background: var(--color-success-light); color: var(--color-success); }
  .badge-warning { background: var(--color-warning-light); color: var(--color-warning); }
  .badge-danger { background: var(--color-danger-light); color: var(--color-danger); }
  .badge-info { background: var(--color-info-light); color: var(--color-info); }
  .badge-neutral { background: var(--bg-tertiary); color: var(--text-secondary); }
  .badge-outline { background: transparent; border: 1px solid currentColor; }

/* ---- Tables ---- */
.table-wrap { overflow-x: auto; }
.table { width: 100%; border-collapse: collapse; font-size: var(--text-sm); }
.table th {
  text-align: left;
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-xs);
  font-weight: var(--font-bold);
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: var(--bg-tertiary);
  border-bottom: 1px solid var(--border-light);
  white-space: nowrap;
}
.table td {
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--border-light);
  vertical-align: middle;
}
.table tbody tr { transition: background var(--transition-fast); }
.table tbody tr:hover { background: var(--bg-tertiary); }
.table .cell-primary { font-weight: var(--font-semibold); color: var(--text-primary); }
.table .cell-muted { color: var(--text-muted); font-size: var(--text-xs); }

/* ---- Alerts ---- */
.alert {
  display: none;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  border: 1px solid;
  animation: slideIn var(--transition-base) ease;
}
.alert.show { display: flex; }
.alert svg { width: 18px; height: 18px; flex-shrink: 0; }
.alert .close { margin-left: auto; background: none; border: none; cursor: pointer; opacity: 0.6; font-size: 1.25rem; line-height: 1; color: inherit; padding: 0; }
.alert .close:hover { opacity: 1; }

.alert-success { background: var(--color-success-light); border-color: var(--color-success-lighter); color: var(--color-success); }
.alert-danger { background: var(--color-danger-light); border-color: var(--color-danger-lighter); color: var(--color-danger); }
.alert-warning { background: var(--color-warning-light); border-color: var(--color-warning-lighter); color: var(--color-warning); }
.alert-info { background: var(--color-info-light); border-color: var(--color-info); color: var(--color-info); }

@keyframes slideIn { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; transform: translateY(0); } }

/* ---- Modal ---- */
.modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.5);
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal);
  padding: var(--space-4);
}
.modal.show { display: flex; }
.modal-card {
  background: var(--bg-secondary);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  width: 100%;
  max-width: 560px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  animation: modalIn var(--transition-base) ease;
}
@keyframes modalIn { from { opacity: 0; transform: scale(0.95); } to { opacity: 1; transform: scale(1); } }
.modal-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: var(--space-4); padding-bottom: var(--space-3); border-bottom: 1px solid var(--border-light); }
.modal-header h3 { margin: 0; font-size: var(--text-xl); font-weight: var(--font-bold); }
.close-modal { background: none; border: none; font-size: 1.5rem; cursor: pointer; color: var(--text-muted); line-height: 1; padding: var(--space-1); }
.close-modal:hover { color: var(--text-primary); }

.view-row { display: grid; grid-template-columns: 140px 1fr; gap: var(--space-3); padding: var(--space-2) 0; border-bottom: 1px solid var(--border-light); font-size: var(--text-sm); }
.view-label { color: var(--text-muted); font-weight: var(--font-semibold); font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.04em; }

/* ---- Pagination ---- */
.pagination { display: flex; align-items: center; justify-content: center; gap: var(--space-1); flex-wrap: wrap; }
.pagination a, .pagination span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 36px;
  padding: 0 var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  text-decoration: none;
  transition: all var(--transition-fast);
}
.pagination a { color: var(--text-secondary); border: 1px solid var(--border-light); background: var(--bg-secondary); }
.pagination a:hover { border-color: var(--color-primary); color: var(--color-primary); background: var(--color-primary-light); }
.pagination .current { background: var(--color-primary); color: var(--color-white); border-color: var(--color-primary); }
.pagination .ellipsis { color: var(--text-muted); border-color: transparent; background: transparent; cursor: default; }
.pagination .prev, .pagination .next { padding: 0 var(--space-3); }

/* ---- Tabs ---- */
.tabs { display: flex; border-bottom: 1px solid var(--border-light); margin-bottom: var(--space-6); }
.tab { padding: var(--space-3) var(--space-4); font-size: var(--text-sm); font-weight: var(--font-medium); color: var(--text-muted); border-bottom: 2px solid transparent; margin-bottom: -1px; transition: all var(--transition-fast); cursor: pointer; }
.tab:hover { color: var(--text-primary); }
.tab.active { color: var(--color-primary); border-bottom-color: var(--color-primary); }

/* ---- Sidebar (Admin) ---- */
.sidebar {
  width: var(--sidebar-width);
  background: var(--color-900);
  color: var(--color-white);
  height: 100vh;
  position: fixed;
  left: 0;
  top: 0;
  padding: var(--space-6) var(--space-4);
  display: flex;
  flex-direction: column;
  z-index: var(--z-fixed);
}
.sidebar .logo {
  width: 44px; height: 44px;
  background: linear-gradient(135deg, var(--color-primary), #6366f1);
  border-radius: var(--radius-md);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: var(--space-6);
}
.sidebar .logo svg { width: 24px; height: 24px; color: var(--color-white); }
.sidebar h2 { font-size: var(--text-sm); font-weight: var(--font-bold); text-transform: uppercase; letter-spacing: 0.05em; color: var(--color-400); margin-bottom: var(--space-4); }
.sidebar nav { display: flex; flex-direction: column; gap: var(--space-1); flex: 1; }
.sidebar nav a {
  display: flex; align-items: center; gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  color: var(--color-400);
  text-decoration: none;
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  transition: all var(--transition-fast);
}
.sidebar nav a:hover { background: rgba(79, 70, 229, 0.15); color: var(--color-white); }
.sidebar nav a.active { background: rgba(79, 70, 229, 0.2); color: var(--color-white); }
.sidebar nav a svg { width: 20px; height: 20px; flex-shrink: 0; }
.sidebar .logout { margin-top: auto; border-top: 1px solid rgba(255,255,255,0.1); padding-top: var(--space-4); }
.main-content { margin-left: var(--sidebar-width); padding: var(--space-8); min-height: 100vh; }

@media (max-width: 900px) {
  .sidebar { display: none; }
  .main-content { margin-left: 0; padding: var(--space-6); }
}

/* ---- Navbar (Student) ---- */
.navbar {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-light);
  padding: 0 var(--space-6);
  height: var(--header-height);
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  box-shadow: var(--shadow-xs);
}
.nav-left { display: flex; align-items: center; gap: var(--space-4); }
.nav-logo { width: 36px; height: 36px; background: linear-gradient(135deg, var(--color-primary), #6366f1); border-radius: var(--radius-md); display: flex; align-items: center; justify-content: center; }
.nav-logo svg { width: 20px; height: 20px; color: var(--color-white); }
.brand { font-weight: var(--font-bold); font-size: var(--text-lg); color: var(--text-primary); }
.nav-link { padding: var(--space-2) var(--space-3); border-radius: var(--radius-md); text-decoration: none; font-size: var(--text-sm); font-weight: var(--font-medium); color: var(--text-muted); transition: all var(--transition-fast); }
.nav-link:hover { background: var(--color-primary-light); color: var(--color-primary); text-decoration: none; }
.nav-link.active { background: var(--color-primary-light); color: var(--color-primary); }
  .nav-right { display: flex; align-items: center; gap: var(--space-4); font-size: var(--text-sm); color: var(--text-muted); }
  .nav-avatar { width: 36px; height: 36px; border-radius: var(--radius-md); background: linear-gradient(135deg, var(--color-primary), #6366f1); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: var(--font-bold); font-size: var(--text-sm); flex-shrink: 0; }
.nav-logout { padding: var(--space-2) var(--space-3); border: 1px solid var(--border-light); border-radius: var(--radius-md); text-decoration: none; color: var(--text-primary); font-weight: var(--font-medium); background: var(--bg-secondary); transition: all var(--transition-fast); }
.nav-logout:hover { border-color: var(--color-primary); color: var(--color-primary); text-decoration: none; }

@media (max-width: 640px) { .brand { display: none; } .nav-right span { display: none; } }

/* ---- Footer ---- */
.footer {
  margin-top: var(--space-12);
  padding: var(--space-6) var(--space-4);
  text-align: center;
  border-top: 1px solid var(--border-light);
  color: var(--text-muted);
  font-size: var(--text-xs);
  background: var(--bg-secondary);
}
  .footer strong { color: var(--text-primary); }

  /* ---- Sidebar User Profile ---- */
  .sidebar-profile {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    margin-bottom: var(--space-5);
    padding: var(--space-3);
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
  }
  .sidebar-profile .avatar {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, var(--color-primary), #6366f1);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: var(--font-bold);
    font-size: var(--text-lg);
    flex-shrink: 0;
  }
  .sidebar-profile .profile-meta { min-width: 0; }
  .sidebar-profile .profile-name {
    display: block;
    font-size: var(--text-sm);
    font-weight: var(--font-semibold);
    color: #fff;
    line-height: 1.2;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
  .sidebar-profile .profile-role { display: block; font-size: var(--text-xs); color: var(--color-400); }

  /* Dark mode variations for action buttons */
  :root[data-theme="dark"] .btn-edit,
  :root[data-theme="dark"] .btn-reset,
  :root[data-theme="dark"] .btn-delete,
  :root[data-theme="dark"] .btn-view,
  :root[data-theme="dark"] .btn-secondary,
  :root[data-theme="dark"] .btn-ghost,
  :root[data-theme="dark"] .btn-outline,
  :root[data-theme="dark"] .btn-primary,
  :root[data-theme="dark"] .btn-success {
    background: var(--color-primary);
    color: var(--text-primary);
  }

  :root[data-theme="dark"] .btn-secondary,
  :root[data-theme="dark"] .btn-ghost,
  :root[data-theme="dark"] .btn-outline {
    background: var(--bg-tertiary);
    color: var(--text-primary);
  }

  :root[data-theme="dark"] .btn-success {
    background: var(--color-success);
    color: var(--color-white);
  }

  :root[data-theme="dark"] .btn-danger {
    background: var(--color-danger);
    color: var(--color-white);
  }

/* ---- Page Headers ---- */
.page-header { margin-bottom: var(--space-6); }
.page-header h1 { font-size: var(--text-2xl); font-weight: var(--font-bold); color: var(--text-primary); margin-bottom: var(--space-1); }
.page-header p { color: var(--text-muted); font-size: var(--text-base); }

/* ---- Stat Cards ---- */
.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: var(--space-4); }
.stat-card { background: var(--bg-secondary); border: 1px solid var(--border-light); border-radius: var(--radius-lg); padding: var(--space-5); text-align: center; transition: all var(--transition-base); }
.stat-card:hover { box-shadow: var(--shadow-md); border-color: var(--border-medium); }
.stat-value { font-size: var(--text-3xl); font-weight: var(--font-extrabold); margin-bottom: var(--space-1); line-height: 1; }
.stat-value.primary { color: var(--color-primary); }
.stat-value.success { color: var(--color-success); }
.stat-value.warning { color: var(--color-warning); }
.stat-value.danger { color: var(--color-danger); }
.stat-label { color: var(--text-muted); font-size: var(--text-xs); font-weight: var(--font-semibold); text-transform: uppercase; letter-spacing: 0.05em; }

/* ---- Empty State ---- */
.empty-state { text-align: center; padding: var(--space-12) var(--space-6); color: var(--text-muted); }
.empty-state svg { width: 64px; height: 64px; margin: 0 auto var(--space-4); color: var(--color-300); }
.empty-state h3 { font-size: var(--text-lg); font-weight: var(--font-semibold); color: var(--text-secondary); margin-bottom: var(--space-2); }
.empty-state p { font-size: var(--text-sm); max-width: 320px; margin: 0 auto; }

/* ---- Search Form ---- */
.search-form { display: flex; gap: var(--space-3); margin-bottom: var(--space-4); align-items: center; flex-wrap: wrap; }
.search-form input { flex: 1; min-width: 200px; max-width: 400px; }

/* ---- Utility Classes ---- */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }
.hidden { display: none !important; }
.invisible { visibility: hidden; }
.overflow-hidden { overflow: hidden; }
.relative { position: relative; }

/* ---- Print ---- */
  @media print {
    .sidebar, .navbar, .btn, .footer, .alert, .pagination, .search-form, .modal { display: none !important; }
    .main-content { margin-left: 0; padding: 0; }
    .card { box-shadow: none; border: 1px solid var(--border-medium); }
    body { background: var(--color-white); }
  }

  /* ==========================================================================
     UNIFICATION HELPERS — legacy variable aliases + shared component extras
     (lets every view resolve a single, consistent design system)
     ========================================================================== */
  :root {
    --primary: var(--color-primary);
    --primary-hover: var(--color-primary-hover);
    --primary-light: var(--color-primary-light);
    --success: var(--color-success);
    --danger: var(--color-danger);
    --warning: var(--color-warning);
    --bg: var(--bg-primary);
    --card: var(--bg-secondary);
    --text: var(--text-primary);
    --text-muted: var(--text-muted);
    --border: var(--border-light);
    --sidebar: var(--color-900);
    --shadow: var(--shadow-md);
    --shadow-lg: var(--shadow-lg);
    --radius: var(--radius-lg);
    --radius-sm: var(--radius-md);
    --transition: var(--transition-base);
  }

  .text-primary { color: var(--color-primary); }
  .fw-bold { font-weight: var(--font-bold); }

  /* Centered auth/standalone card (change-password, etc.) */
  .auth-wrap {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-6);
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--color-100) 100%);
  }
  .auth-wrap .card { width: 100%; max-width: 440px; padding: var(--space-8); }
  .auth-wrap .card h2 { font-size: var(--text-2xl); font-weight: var(--font-extrabold); margin-bottom: var(--space-1); letter-spacing: -0.02em; }
  .auth-wrap .back { display: inline-block; margin-top: var(--space-4); font-size: var(--text-sm); font-weight: var(--font-semibold); color: var(--color-primary); }
  .auth-wrap .back:hover { color: var(--color-primary-hover); text-decoration: underline; }

  .hint { font-size: var(--text-xs); color: var(--text-muted); margin-top: var(--space-1); }

  /* User-management table action buttons + badges */
  .btn-view { background: var(--color-info-light); color: var(--color-info); }
  .btn-view:hover:not(:disabled) { background: #a5f3fc; }
  .btn-edit { background: var(--color-primary-light); color: var(--color-primary-dark); }
  .btn-edit:hover:not(:disabled) { background: var(--color-primary-lighter); }
  .btn-reset { background: var(--color-warning-light); color: var(--color-warning); }
  .btn-reset:hover:not(:disabled) { background: var(--color-warning-lighter); }
  .btn-delete { background: var(--color-danger-light); color: var(--color-danger); }
  .btn-delete:hover:not(:disabled) { background: var(--color-danger-lighter); }

  .actions { display: flex; gap: var(--space-2); flex-wrap: wrap; justify-content: flex-end; }

  .subjects-edit {
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: var(--space-3);
    max-height: 180px;
    overflow-y: auto;
    background: var(--bg-tertiary);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-2);
  }
  .subjects-edit label {
    display: flex;
    gap: var(--space-2);
    align-items: center;
    font-size: var(--text-sm);
    background: var(--bg-secondary);
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-light);
    cursor: pointer;
  }
  .subjects-edit input { accent-color: var(--color-primary); width: 16px; height: 16px; flex-shrink: 0; }

  .badge-subj { background: var(--color-primary); color: var(--color-white); }
  .badge-set { background: var(--color-warning-light); color: var(--color-warning); }
  .badge-role { background: var(--bg-tertiary); color: var(--text-secondary); }
  .badge-admin { background: var(--color-warning-light); color: var(--color-warning); }


/* ==========================================================================
   EXAM PAGE — Professional Student Exam UI
   ========================================================================== */

.exam-shell { display: flex; flex-direction: column; min-height: 100vh; background: var(--bg-primary); }

/* Header */
.exam-header { position: sticky; top: 0; z-index: 20; background: var(--bg-secondary); border-bottom: 1px solid var(--border-light); padding: var(--space-4) var(--space-6); display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); flex-wrap: wrap; box-shadow: var(--shadow-sm); }
.exam-header-left { display: flex; flex-direction: column; gap: var(--space-1); min-width: 0; }
.exam-title { font-size: var(--text-xl); font-weight: var(--font-bold); color: var(--text-primary); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.exam-subject { font-size: var(--text-sm); color: var(--text-muted); font-weight: var(--font-medium); background: var(--color-primary-light); color: var(--color-primary); padding: 2px 10px; border-radius: var(--radius-full); display: inline-block; width: fit-content; }
.exam-timer { flex-shrink: 0; text-align: center; }
.timer-display { font-size: 2.25rem; font-weight: var(--font-extrabold); color: var(--color-primary); font-variant-numeric: tabular-nums; font-family: var(--font-mono); letter-spacing: -0.03em; transition: color var(--transition-base); background: linear-gradient(135deg, var(--color-primary-light), transparent); padding: 8px 16px; border-radius: var(--radius-md); min-width: 110px; display: inline-block; }
.timer-display.urgent { color: var(--color-danger); background: linear-gradient(135deg, var(--color-danger-light), transparent); animation: pulse 1s infinite; }
.timer-label { font-size: var(--text-xs); color: var(--text-muted); font-weight: var(--font-medium); text-transform: uppercase; letter-spacing: 0.08em; margin-top: 4px; }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.6; } }

/* Progress Bar */
.exam-progress { height: 4px; background: var(--bg-tertiary); overflow: hidden; position: relative; }
.exam-progress::after { content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0; background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.3) 50%, transparent 100%); animation: shimmer 2s infinite; }
@keyframes shimmer { 0% { transform: translateX(-100%); } 100% { transform: translateX(100%); } }
.exam-progress-fill { height: 100%; background: linear-gradient(90deg, var(--color-primary), var(--color-primary-hover)); border-radius: var(--radius-full); transition: width 0.3s ease; width: 0%; position: relative; z-index: 1; }

/* Main */
.exam-main { flex: 1; padding: var(--space-6); overflow-y: auto; max-width: 960px; margin: 0 auto; width: 100%; display: flex; flex-direction: column; min-height: 0; }

/* Slides Container */
.slides-container { flex: 1; display: flex; flex-direction: column; min-height: 0; }

/* Question Slide */
.question-slide { display: none !important; animation: slideIn 200ms cubic-bezier(0.16, 1, 0.3, 1); }
.question-slide.active { display: flex !important; flex-direction: column; }
@keyframes slideIn { from { opacity: 0; transform: translateX(20px); } to { opacity: 1; transform: translateX(0); } }

.question-card { background: var(--bg-secondary); border: 1px solid var(--border-light); border-radius: var(--radius-xl); padding: var(--space-6); box-shadow: var(--shadow-sm); flex: 1; display: flex; flex-direction: column; transition: box-shadow var(--transition-base), border-color var(--transition-base); }
.question-card:hover { box-shadow: var(--shadow-md); border-color: var(--border-medium); }

.q-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: var(--space-5); flex-wrap: wrap; gap: var(--space-2); }
.q-number { background: var(--color-primary); color: var(--color-white); padding: 6px 14px; border-radius: var(--radius-full); font-size: var(--text-xs); font-weight: var(--font-bold); letter-spacing: 0.05em; box-shadow: var(--shadow-xs); }
.q-count { font-size: var(--text-sm); color: var(--text-muted); font-weight: var(--font-medium); background: var(--bg-tertiary); padding: 4px 12px; border-radius: var(--radius-full); }

.question-text { font-size: var(--text-xl); font-weight: var(--font-semibold); color: var(--text-primary); margin-bottom: var(--space-6); line-height: 1.65; letter-spacing: -0.01em; }

/* Options */
.options { display: flex; flex-direction: column; gap: var(--space-3); flex: 1; }
.option { display: flex; align-items: center; padding: var(--space-4) var(--space-5); background: var(--bg-secondary); border: 2px solid var(--border-light); border-radius: var(--radius-lg); cursor: pointer; transition: all var(--transition-fast); font-size: var(--text-base); color: var(--text-secondary); position: relative; }
.option::before { content: ''; position: absolute; left: 0; top: 0; bottom: 0; width: 4px; background: transparent; border-radius: var(--radius-lg) 0 0 var(--radius-lg); transition: background var(--transition-fast); }
.option:hover { background: var(--color-primary-light); border-color: var(--color-primary-lighter); color: var(--text-primary); transform: translateX(2px); }
.option.selected { background: var(--color-primary-light); border-color: var(--color-primary); color: var(--text-primary); box-shadow: 0 0 0 3px var(--color-primary-light); }
.option.selected::before { background: var(--color-primary); }
.option input { margin-right: var(--space-4); accent-color: var(--color-primary); width: 20px; height: 20px; flex-shrink: 0; cursor: pointer; }
.option-label { flex: 1; font-weight: var(--font-medium); }
.option-marker { color: var(--color-primary); font-weight: var(--font-bold); margin-right: var(--space-2); font-family: var(--font-mono); font-size: var(--text-base); min-width: 28px; }

/* Nav Dots */
.nav-dots { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; padding: var(--space-4) var(--space-6); margin-top: auto; border-top: 1px solid var(--border-light); background: var(--bg-secondary); }
.nav-dot { width: 40px; height: 40px; border-radius: var(--radius-md); border: 2px solid var(--border-light); background: var(--bg-secondary); display: flex; align-items: center; justify-content: center; font-size: var(--text-sm); font-weight: var(--font-bold); color: var(--text-muted); cursor: pointer; transition: all var(--transition-fast); user-select: none; position: relative; overflow: hidden; }
.nav-dot::after { content: ''; position: absolute; inset: 0; background: var(--color-primary); transform: scale(0); border-radius: inherit; transition: transform var(--transition-fast); z-index: -1; }
.nav-dot:hover { border-color: var(--color-primary); color: var(--color-primary); transform: translateY(-2px); box-shadow: var(--shadow-sm); }
.nav-dot.active { color: var(--color-white); border-color: var(--color-primary); transform: scale(1.1); box-shadow: 0 0 0 4px var(--color-primary-light); }
.nav-dot.active::after { transform: scale(1); }
.nav-dot.answered:not(.active) { background: var(--color-success-light); border-color: var(--color-success); color: var(--color-success); }
.nav-dot.answered:not(.active)::after { background: var(--color-success); }
.nav-dot.flagged { box-shadow: 0 0 0 2px var(--color-warning); }
.nav-dot.flagged::before { content: '⚑'; position: absolute; top: -4px; right: -4px; font-size: 10px; color: var(--color-warning); background: var(--color-white); border-radius: 50%; width: 16px; height: 16px; display: flex; align-items: center; justify-content: center; }

/* Slide Navigation */
.slide-nav { display: flex; gap: var(--space-3); padding: var(--space-4) var(--space-6); border-top: 1px solid var(--border-light); background: var(--bg-secondary); position: sticky; bottom: 0; z-index: 10; flex-wrap: wrap; }
.nav-btn { flex: 1; min-width: 140px; padding: var(--space-3) var(--space-6); font-size: var(--text-base); font-weight: var(--font-semibold); border-radius: var(--radius-lg); border: none; cursor: pointer; transition: all var(--transition-fast); display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2); box-shadow: var(--shadow-xs); }
.nav-btn:disabled { opacity: 0.4; cursor: not-allowed; transform: none !important; }
.nav-btn:not(:disabled):hover { transform: translateY(-1px); box-shadow: var(--shadow-md); }
.nav-btn:not(:disabled):active { transform: translateY(0); }
.nav-btn svg { width: 20px; height: 20px; flex-shrink: 0; }
.btn-prev { background: var(--bg-tertiary); color: var(--text-secondary); border: 2px solid var(--border-light); }
.btn-prev:hover:not(:disabled) { background: var(--border-light); color: var(--text-primary); border-color: var(--border-medium); }
.btn-next { background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover)); color: var(--color-white); }
.btn-next:hover:not(:disabled) { background: linear-gradient(135deg, var(--color-primary-hover), var(--color-primary-dark)); }
.btn-submit { background: linear-gradient(135deg, var(--color-success), var(--color-success-hover)); color: var(--color-white); width: 100%; }
.btn-submit:hover:not(:disabled) { background: linear-gradient(135deg, var(--color-success-hover), #047857); }

/* Review Modal */
.review-modal .modal-card { max-width: 760px; }
.review-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: var(--space-4); }
.review-title { font-size: var(--text-xl); font-weight: var(--font-bold); }
.review-stats { display: flex; gap: var(--space-3); font-size: var(--text-sm); flex-wrap: wrap; }
.review-stat { display: inline-flex; align-items: center; gap: var(--space-2); padding: var(--space-2) var(--space-3); border-radius: var(--radius-full); font-weight: var(--font-semibold); font-size: var(--text-sm); box-shadow: var(--shadow-xs); }
.review-stat.answered { background: var(--color-success-light); color: var(--color-success); border: 1px solid var(--color-success-lighter); }
.review-stat.unanswered { background: var(--bg-tertiary); color: var(--text-muted); border: 1px solid var(--border-light); }
.review-stat.flagged { background: var(--color-warning-light); color: var(--color-warning); border: 1px solid var(--color-warning-lighter); }
.review-grid { display: grid; grid-template-columns: repeat(10, 1fr); gap: 10px; margin-bottom: var(--space-5); }
.review-dot { aspect-ratio: 1; border-radius: var(--radius-md); border: 2px solid; display: flex; align-items: center; justify-content: center; font-size: 13px; font-weight: var(--font-bold); cursor: pointer; transition: all var(--transition-fast); user-select: none; background: var(--bg-secondary); position: relative; }
.review-dot.answered { background: var(--color-success-light); border-color: var(--color-success); color: var(--color-success); }
.review-dot.unanswered { background: var(--bg-tertiary); border-color: var(--border-medium); color: var(--text-muted); }
.review-dot.flagged { background: var(--color-warning-light); border-color: var(--color-warning); color: var(--color-warning); }
.review-dot.current { box-shadow: 0 0 0 3px var(--color-primary); z-index: 1; }
.review-dot:hover { transform: scale(1.15); box-shadow: var(--shadow-md); }
.review-dot::before { content: ''; position: absolute; top: -3px; right: -3px; width: 10px; height: 10px; background: var(--color-warning); border-radius: 50%; display: none; }
.review-dot.flagged::before { display: block; }
.review-legend { display: flex; gap: var(--space-4); justify-content: center; font-size: var(--text-xs); color: var(--text-muted); margin-bottom: var(--space-4); flex-wrap: wrap; }
.review-legend-item { display: inline-flex; align-items: center; gap: var(--space-1); }
.review-legend-dot { width: 16px; height: 16px; border-radius: var(--radius-sm); border: 2px solid; }
.review-actions { display: flex; justify-content: flex-end; gap: var(--space-3); padding-top: var(--space-4); border-top: 1px solid var(--border-light); }

/* Time-up Overlay */
.timeup-overlay { position: fixed; inset: 0; background: rgba(15, 23, 42, 0.9); display: flex; align-items: center; justify-content: center; z-index: 1000; animation: fadeIn 300ms ease; backdrop-filter: blur(4px); }
.timeup-card { background: var(--bg-secondary); padding: var(--space-12) var(--space-10); border-radius: var(--radius-xl); text-align: center; max-width: 460px; box-shadow: var(--shadow-xl); animation: scaleIn 300ms cubic-bezier(0.16, 1, 0.3, 1); }
@keyframes scaleIn { from { opacity: 0; transform: scale(0.9); } to { opacity: 1; transform: scale(1); } }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
.timeup-icon { width: 80px; height: 80px; margin: 0 auto var(--space-5); color: var(--color-danger); animation: bounce 1s ease-in-out infinite; }
@keyframes bounce { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-8px); } }
.timeup-title { font-size: var(--text-3xl); font-weight: var(--font-extrabold); color: var(--text-primary); margin-bottom: var(--space-2); letter-spacing: -0.02em; }
.timeup-message { color: var(--text-secondary); margin-bottom: var(--space-8); font-size: var(--text-lg); }
.timeup-btn { background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover)); color: var(--color-white); padding: var(--space-4) var(--space-10); border-radius: var(--radius-lg); font-weight: var(--font-bold); border: none; cursor: pointer; font-size: var(--text-base); box-shadow: var(--shadow-md); transition: all var(--transition-fast); }
.timeup-btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }

/* Helper */
.d-inline { display: inline-flex; }

/* Responsive */
@media (max-width: 768px) {
  .exam-header { padding: var(--space-3) var(--space-4); }
  .timer-display { font-size: 1.75rem; padding: 6px 12px; min-width: 90px; }
  .exam-main { padding: var(--space-4); }
  .question-card { padding: var(--space-5); }
  .question-text { font-size: var(--text-lg); }
  .option { padding: var(--space-3) var(--space-4); }
  .slide-nav { flex-direction: column; padding: var(--space-3) var(--space-4); gap: var(--space-2); }
  .nav-btn { width: 100%; min-width: 0; }
  .nav-dot { width: 36px; height: 36px; font-size: var(--text-xs); }
  .nav-dots { padding: var(--space-3) var(--space-4); gap: 6px; }
  .review-grid { grid-template-columns: repeat(8, 1fr); gap: 8px; }
  .timeup-card { padding: var(--space-8) var(--space-6); margin: var(--space-4); }
}

@media (max-width: 480px) {
  .exam-title { font-size: var(--text-lg); }
  .q-number { font-size: 10px; padding: 4px 10px; }
  .question-text { font-size: var(--text-base); }
  .option { padding: var(--space-3) var(--space-3); font-size: var(--text-sm); }
  .option-marker { min-width: 24px; font-size: var(--text-sm); }
  .timer-display { font-size: 1.5rem; }
  .btn-prev, .btn-next, .btn-submit { padding: var(--space-3) var(--space-4); }
}

/* --------------------------------------------------------------------------
   SHARED EXAM + QUIZ SHELL — mobile & touch refinements
   Both pages use the same .exam-* shell, so these rules cover both.
   -------------------------------------------------------------------------- */

/* Dynamic viewport height: mobile browser bars no longer clip the page */
.exam-shell { min-height: 100dvh; }

/* Long question / choice text must never overflow its card */
.question-text, .option, .option-label { overflow-wrap: anywhere; }
.option-label { min-width: 0; }
.option-marker { flex-shrink: 0; }

/* Snappier taps: no 300ms delay, no accidental double-tap zoom */
.option, .nav-btn, .nav-dot, .review-dot, .timeup-btn, .close-modal { touch-action: manipulation; }

/* Sticky bottom bar clears the phone home-indicator area */
.slide-nav { padding-bottom: calc(var(--space-4) + env(safe-area-inset-bottom, 0px)); }

/* Touch devices: neutralise sticky :hover states (they stay "stuck" after a tap) */
@media (hover: none) {
  .option:hover { background: var(--bg-secondary); border-color: var(--border-light); color: var(--text-secondary); transform: none; }
  .option.selected:hover { background: var(--color-primary-light); border-color: var(--color-primary); color: var(--text-primary); }
  .nav-dot:hover { transform: none; box-shadow: none; }
  .nav-btn:not(:disabled):hover { transform: none; box-shadow: var(--shadow-xs); }
  .review-dot:hover { transform: none; box-shadow: none; }
}

@media (max-width: 768px) {
  /* Title on its own row; timer right-aligned underneath, still large enough to read */
  .exam-header { gap: var(--space-2); padding-top: calc(var(--space-3) + env(safe-area-inset-top, 0px)); }
  .exam-header-left { flex: 1 1 100%; }
  .exam-title { white-space: normal; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; line-height: 1.3; }
  .exam-timer { margin-left: auto; }
  .exam-main { padding: var(--space-4) var(--space-3); }
  .question-card { padding: var(--space-4); border-radius: var(--radius-lg); }
  .option { min-height: 52px; }
  .option input { width: 22px; height: 22px; margin-right: var(--space-3); }
  .nav-btn { min-height: 48px; }
  .slide-nav { padding-bottom: calc(var(--space-3) + env(safe-area-inset-bottom, 0px)); }
  .review-modal .modal-card { padding: var(--space-5); }
  .review-actions { flex-direction: column-reverse; }
  .review-actions .btn { width: 100%; }
  .timeup-btn { width: 100%; }
}

@media (max-width: 480px) {
  .timer-display { font-size: 1.45rem; min-width: 84px; }
  .exam-subject { font-size: var(--text-xs); }
  .q-count { padding: 3px 10px; }
  .option { min-height: 48px; }
  .review-grid { grid-template-columns: repeat(5, 1fr); gap: 6px; }
  .review-stats { gap: var(--space-2); }
  .review-stat { padding: 4px 10px; font-size: var(--text-xs); }
  .timeup-card { padding: var(--space-6) var(--space-4); }
  .timeup-icon { width: 56px; height: 56px; margin-bottom: var(--space-4); }
  .timeup-title { font-size: var(--text-2xl); }
  .timeup-message { font-size: var(--text-base); margin-bottom: var(--space-6); }
}

/* Very small phones (320px / foldable cover screens) */
@media (max-width: 360px) {
  .nav-dot { width: 34px; height: 34px; }
  .review-grid { grid-template-columns: repeat(4, 1fr); }
  .timer-display { font-size: 1.3rem; min-width: 76px; padding: 4px 10px; }
  .question-card { padding: var(--space-3); }
}

/* Landscape phones: compact header, nav buttons back on a single row */
@media (max-height: 520px) and (orientation: landscape) {
  .exam-header { position: static; padding: var(--space-2) var(--space-4); }
  .exam-header-left { flex: 1 1 auto; }
  .exam-timer { margin-left: 0; }
  .exam-title { white-space: nowrap; display: block; }
  .timer-display { font-size: 1.35rem; min-width: 78px; padding: 4px 10px; }
  .exam-main { padding: var(--space-3); }
  .nav-dots { display: none; }
  .slide-nav { flex-direction: row; padding-bottom: var(--space-2); }
  .nav-btn { width: auto; min-width: 0; min-height: 42px; }
}

/* ==========================================================================
   UI NOTIFICATIONS — Toasts & Confirm Dialog
   ========================================================================== */
.ui-toast-container { position: fixed; top: var(--space-4); right: var(--space-4); z-index: 10002; display: flex; flex-direction: column; gap: var(--space-3); max-width: min(92vw, 390px); pointer-events: none; }
.ui-toast { pointer-events: auto; display: flex; align-items: flex-start; gap: var(--space-3); background: var(--bg-secondary); border: 1px solid var(--border-light); border-left: 4px solid var(--color-info); border-radius: var(--radius-lg); padding: var(--space-3) var(--space-4); box-shadow: var(--shadow-xl); transform: translateX(110%); opacity: 0; transition: transform 260ms cubic-bezier(0.16, 1, 0.3, 1), opacity 220ms ease; max-width: 100%; }
.ui-toast.show { transform: translateX(0); opacity: 1; }
.ui-toast.leaving { transform: translateX(110%); opacity: 0; }
.ui-toast-success { border-left-color: var(--color-success); }
.ui-toast-error { border-left-color: var(--color-danger); }
.ui-toast-warning { border-left-color: var(--color-warning); }
.ui-toast-info { border-left-color: var(--color-info); }
.ui-toast-icon { flex-shrink: 0; width: 22px; height: 22px; margin-top: 1px; }
.ui-toast-icon svg { width: 22px; height: 22px; }
.ui-toast-success .ui-toast-icon { color: var(--color-success); }
.ui-toast-error .ui-toast-icon { color: var(--color-danger); }
.ui-toast-warning .ui-toast-icon { color: var(--color-warning); }
.ui-toast-info .ui-toast-icon { color: var(--color-info); }
.ui-toast-body { flex: 1; min-width: 0; }
.ui-toast-title { font-weight: var(--font-bold); font-size: var(--text-sm); color: var(--text-primary); letter-spacing: -0.01em; }
.ui-toast-message { font-size: var(--text-sm); color: var(--text-secondary); margin-top: 2px; line-height: 1.45; overflow-wrap: break-word; }
.ui-toast-close { background: none; border: none; cursor: pointer; color: var(--text-muted); font-size: 1.15rem; line-height: 1; padding: 0 0 0 var(--space-2); flex-shrink: 0; }
.ui-toast-close:hover { color: var(--text-primary); }

.ui-confirm-backdrop { position: fixed; inset: 0; background: rgba(15, 23, 42, 0.55); backdrop-filter: blur(3px); display: flex; align-items: center; justify-content: center; z-index: 10003; padding: var(--space-4); opacity: 0; transition: opacity 200ms ease; }
.ui-confirm-backdrop.show { opacity: 1; }
.ui-confirm-backdrop.leaving { opacity: 0; }
.ui-confirm-box { background: var(--bg-secondary); border: 1px solid var(--border-light); border-radius: var(--radius-xl); box-shadow: var(--shadow-xl); padding: var(--space-8) var(--space-8) var(--space-6); width: min(92vw, 430px); text-align: center; transform: scale(0.92); transition: transform 220ms cubic-bezier(0.16, 1, 0.3, 1); }
.ui-confirm-backdrop.show .ui-confirm-box { transform: scale(1); }
.ui-confirm-icon { width: 56px; height: 56px; margin: 0 auto var(--space-5); border-radius: 50%; background: var(--color-primary-light); color: var(--color-primary); display: flex; align-items: center; justify-content: center; }
.ui-confirm-icon.danger { background: var(--color-danger-light); color: var(--color-danger); }
.ui-confirm-icon svg { width: 28px; height: 28px; }
.ui-confirm-message { font-size: var(--text-base); color: var(--text-primary); font-weight: var(--font-medium); line-height: 1.55; margin-bottom: var(--space-6); overflow-wrap: break-word; }
.ui-confirm-actions { display: flex; gap: var(--space-3); justify-content: center; }
.ui-btn { padding: var(--space-3) var(--space-5); border-radius: var(--radius-md); font-weight: var(--font-semibold); font-size: var(--text-base); cursor: pointer; border: 1px solid var(--border-light); background: var(--bg-secondary); color: var(--text-secondary); transition: all var(--transition-fast); font-family: var(--font-sans); }
.ui-btn:hover { background: var(--bg-tertiary); }
.ui-btn-ok { background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover)); color: var(--color-white); border-color: transparent; }
.ui-btn-ok:hover { background: linear-gradient(135deg, var(--color-primary-hover), var(--color-primary-dark)); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.ui-btn-ok.danger { background: linear-gradient(135deg, var(--color-danger), var(--color-danger-hover)); }
.ui-btn-ok.danger:hover { background: linear-gradient(135deg, var(--color-danger-hover), var(--color-danger)); }

@media print {
  .ui-toast-container, .ui-confirm-backdrop { display: none !important; }
}