/* =========================================================
   GyanBazi — Professional EdTech Platform
   Light Theme | Clean | Modern | Trustworthy
   Version: 1.0.0
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* ─── CSS DESIGN TOKENS ──────────────────────────────────── */
:root {
  /* Primary Palette */
  --primary:          #2563EB;
  --primary-hover:    #1D4ED8;
  --primary-light:    #EFF6FF;
  --primary-border:   #BFDBFE;

  /* Accent */
  --accent:           #0EA5E9;
  --accent-light:     #E0F2FE;

  /* Semantic */
  --success:          #16A34A;
  --success-light:    #DCFCE7;
  --warning:          #D97706;
  --warning-light:    #FEF3C7;
  --danger:           #DC2626;
  --danger-light:     #FEE2E2;
  --info:             #0891B2;
  --info-light:       #CFFAFE;

  /* Neutrals */
  --bg:               #F8FAFC;
  --bg-card:          #FFFFFF;
  --bg-subtle:        #F1F5F9;
  --bg-hover:         #F8FAFC;
  --border:           #E2E8F0;
  --border-strong:    #CBD5E1;

  /* Text */
  --text-primary:     #0F172A;
  --text-secondary:   #475569;
  --text-muted:       #94A3B8;
  --text-placeholder: #CBD5E1;

  /* Gamification */
  --gold:             #F59E0B;
  --gold-light:       #FEF3C7;
  --silver:           #94A3B8;
  --bronze:           #B45309;
  --streak-orange:    #F97316;
  --streak-bg:        #FFF7ED;

  /* Layout */
  --sidebar-w:        260px;
  --topbar-h:         64px;
  --radius-sm:        6px;
  --radius-md:        10px;
  --radius-lg:        14px;
  --radius-xl:        20px;
  --radius-full:      9999px;

  /* Shadows */
  --shadow-xs:        0 1px 2px rgba(0,0,0,0.05);
  --shadow-sm:        0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md:        0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.04);
  --shadow-lg:        0 10px 15px rgba(0,0,0,0.07), 0 4px 6px rgba(0,0,0,0.04);
  --shadow-xl:        0 20px 25px rgba(0,0,0,0.08), 0 10px 10px rgba(0,0,0,0.03);

  /* Transitions */
  --transition:       0.2s ease;
  --transition-slow:  0.35s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--text-primary);
  background: var(--bg);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }
button { font-family: inherit; cursor: pointer; }
input, textarea, select { font-family: inherit; }

h1, h2, h3, h4, h5, h6 {
  line-height: 1.25;
  font-weight: 700;
  color: var(--text-primary);
}

/* Scrollbar */
::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: var(--bg-subtle); }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }

/* ─── LAYOUT UTILITIES ──────────────────────────────────── */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.container-sm { max-width: 720px; margin: 0 auto; padding: 0 24px; }
.container-lg { max-width: 1400px; margin: 0 auto; padding: 0 32px; }

.flex { display: flex; }
.flex-col { display: flex; flex-direction: column; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.gap-4 { gap: 4px; }
.gap-8 { gap: 8px; }
.gap-12 { gap: 12px; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }
.text-center { text-align: center; }
.w-full { width: 100%; }
.hidden { display: none !important; }

/* ─── BUTTONS ───────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 600;
  border: 1px solid transparent;
  transition: all var(--transition);
  white-space: nowrap;
  cursor: pointer;
  text-decoration: none;
  line-height: 1;
}
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-primary {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
  box-shadow: 0 1px 2px rgba(37,99,235,0.2);
}
.btn-primary:hover:not(:disabled) {
  background: var(--primary-hover);
  border-color: var(--primary-hover);
  box-shadow: 0 4px 12px rgba(37,99,235,0.3);
  transform: translateY(-1px);
}

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

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

.btn-danger {
  background: var(--danger);
  color: white;
  border-color: var(--danger);
}
.btn-danger:hover:not(:disabled) {
  background: #B91C1C;
  transform: translateY(-1px);
}

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

.btn-sm { padding: 6px 14px; font-size: 0.8125rem; }
.btn-lg { padding: 13px 28px; font-size: 0.9375rem; }
.btn-xl { padding: 16px 36px; font-size: 1rem; border-radius: var(--radius-lg); }

.btn-icon {
  padding: 8px;
  border-radius: var(--radius-md);
}

.btn-google {
  background: white;
  color: var(--text-primary);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  font-size: 1rem;
  padding: 14px 28px;
  border-radius: var(--radius-lg);
  width: 100%;
  justify-content: center;
  gap: 12px;
}
.btn-google:hover {
  background: var(--bg-subtle);
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}
.btn-google img { width: 20px; height: 20px; }

/* ─── FORM ELEMENTS ─────────────────────────────────────── */
.form-group { display: flex; flex-direction: column; gap: 6px; }

.form-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.form-input, .form-select, .form-textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  color: var(--text-primary);
  background: white;
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
}
.form-input:focus, .form-select:focus, .form-textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}
.form-input::placeholder { color: var(--text-placeholder); }
.form-textarea { resize: vertical; min-height: 100px; }

.form-select { appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2394A3B8'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 12px center; background-size: 16px; padding-right: 40px; }

.form-hint { font-size: 0.8rem; color: var(--text-muted); }
.form-error { font-size: 0.8rem; color: var(--danger); }

/* ─── BADGES & PILLS ────────────────────────────────────── */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
  line-height: 1;
}
.badge-primary { background: var(--primary-light); color: var(--primary); }
.badge-success { background: var(--success-light); color: var(--success); }
.badge-warning { background: var(--warning-light); color: var(--warning); }
.badge-danger  { background: var(--danger-light); color: var(--danger); }
.badge-info    { background: var(--info-light); color: var(--info); }
.badge-neutral { background: var(--bg-subtle); color: var(--text-secondary); }
.badge-gold    { background: var(--gold-light); color: var(--gold); }

/* Difficulty badges */
.badge-easy   { background: #DCFCE7; color: #15803D; }
.badge-medium { background: #FEF3C7; color: #B45309; }
.badge-hard   { background: #FEE2E2; color: #B91C1C; }

/* ─── CARDS ─────────────────────────────────────────────── */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.card-padded { padding: 24px; }
.card-header { padding: 20px 24px; border-bottom: 1px solid var(--border); }
.card-body { padding: 24px; }
.card-footer { padding: 16px 24px; border-top: 1px solid var(--border); background: var(--bg-subtle); border-radius: 0 0 var(--radius-lg) var(--radius-lg); }

/* Stat Cards */
.stat-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: flex-start;
  gap: 16px;
  transition: box-shadow var(--transition);
}
.stat-card:hover { box-shadow: var(--shadow-md); }

.stat-icon {
  width: 48px; height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  flex-shrink: 0;
}
.stat-icon-blue   { background: var(--primary-light); }
.stat-icon-green  { background: var(--success-light); }
.stat-icon-orange { background: var(--warning-light); }
.stat-icon-purple { background: #F3E8FF; }
.stat-icon-cyan   { background: var(--accent-light); }

.stat-content { flex: 1; min-width: 0; }
.stat-label { font-size: 0.8125rem; color: var(--text-muted); font-weight: 500; margin-bottom: 4px; }
.stat-value { font-size: 1.75rem; font-weight: 800; color: var(--text-primary); line-height: 1; font-family: 'JetBrains Mono', monospace; }
.stat-sub { font-size: 0.775rem; color: var(--text-muted); margin-top: 4px; }
.stat-trend { font-size: 0.775rem; font-weight: 600; }
.stat-trend.up { color: var(--success); }
.stat-trend.down { color: var(--danger); }

/* ─── NAVIGATION (PUBLIC) ───────────────────────────────── */
.topnav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--topbar-h);
  background: white;
  border-bottom: 1px solid var(--border);
  z-index: 100;
  box-shadow: var(--shadow-xs);
}

.topnav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  padding: 0 32px;
}

.topnav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}
.topnav-logo {
  width: 36px; height: 36px;
  background: var(--primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: -0.5px;
}
.topnav-name {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
}
.topnav-name span { color: var(--primary); }

.topnav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}
.topnav-links a {
  padding: 7px 14px;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition);
}
.topnav-links a:hover { color: var(--text-primary); background: var(--bg-subtle); }
.topnav-links a.active { color: var(--primary); background: var(--primary-light); }

.topnav-actions { display: flex; align-items: center; gap: 10px; }

/* ─── SIDEBAR LAYOUT (DASHBOARD) ───────────────────────── */
.app-layout {
  display: flex;
  min-height: 100vh;
  background: var(--bg);
}

.sidebar {
  width: var(--sidebar-w);
  background: white;
  border-right: 1px solid var(--border);
  position: fixed;
  top: 0; left: 0; bottom: 0;
  z-index: 50;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  transition: transform var(--transition-slow);
}

.sidebar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 18px 20px;
  border-bottom: 1px solid var(--border);
  min-height: var(--topbar-h);
}
.sidebar-logo {
  width: 36px; height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 800;
  font-size: 0.9rem;
  flex-shrink: 0;
}
.sidebar-name { font-size: 0.95rem; font-weight: 700; color: var(--text-primary); }
.sidebar-tagline { font-size: 0.7rem; color: var(--text-muted); }

.sidebar-nav { flex: 1; padding: 16px 12px; }

.sidebar-section-title {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  padding: 0 10px;
  margin: 16px 0 6px;
}
.sidebar-section-title:first-child { margin-top: 0; }

.sidebar-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition);
  margin-bottom: 2px;
  text-decoration: none;
}
.sidebar-link:hover {
  color: var(--text-primary);
  background: var(--bg-subtle);
}
.sidebar-link.active {
  color: var(--primary);
  background: var(--primary-light);
  font-weight: 600;
}
.sidebar-link .icon {
  width: 20px; height: 20px;
  flex-shrink: 0;
  opacity: 0.75;
}
.sidebar-link.active .icon { opacity: 1; }

.sidebar-link .badge-count {
  margin-left: auto;
  background: var(--primary);
  color: white;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: var(--radius-full);
}

.sidebar-footer {
  padding: 16px 12px;
  border-top: 1px solid var(--border);
}

.sidebar-user {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background var(--transition);
}
.sidebar-user:hover { background: var(--bg-subtle); }
.sidebar-avatar {
  width: 36px; height: 36px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.875rem;
  color: var(--primary);
  flex-shrink: 0;
}
.sidebar-user-info { flex: 1; min-width: 0; }
.sidebar-user-name { font-size: 0.8375rem; font-weight: 600; color: var(--text-primary); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.sidebar-user-email { font-size: 0.75rem; color: var(--text-muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

/* Main Content Area */
.main-content {
  margin-left: var(--sidebar-w);
  flex: 1;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.page-topbar {
  height: var(--topbar-h);
  background: white;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 28px;
  position: sticky;
  top: 0;
  z-index: 40;
  box-shadow: var(--shadow-xs);
}

.page-title { font-size: 1.05rem; font-weight: 700; color: var(--text-primary); }
.page-subtitle { font-size: 0.8rem; color: var(--text-muted); }

.topbar-right { display: flex; align-items: center; gap: 12px; }

.page-body { padding: 28px; flex: 1; }
.page-body-sm { padding: 20px; }

/* ─── DASHBOARD ─────────────────────────────────────────── */
.welcome-banner {
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  border-radius: var(--radius-xl);
  padding: 28px 32px;
  color: white;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  overflow: hidden;
  position: relative;
}
.welcome-banner::before {
  content: '';
  position: absolute;
  top: -40px; right: -40px;
  width: 200px; height: 200px;
  background: rgba(255,255,255,0.08);
  border-radius: 50%;
}
.welcome-banner::after {
  content: '';
  position: absolute;
  bottom: -60px; right: 80px;
  width: 150px; height: 150px;
  background: rgba(255,255,255,0.06);
  border-radius: 50%;
}
.welcome-text { position: relative; z-index: 1; }
.welcome-greeting { font-size: 0.875rem; opacity: 0.85; margin-bottom: 4px; }
.welcome-name { font-size: 1.6rem; font-weight: 800; margin-bottom: 8px; }
.welcome-sub { font-size: 0.875rem; opacity: 0.8; }
.welcome-action { position: relative; z-index: 1; }
.welcome-action .btn { background: white; color: var(--primary); border: none; font-weight: 700; }
.welcome-action .btn:hover { background: var(--bg-subtle); transform: translateY(-2px); box-shadow: 0 4px 12px rgba(0,0,0,0.15); }

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 24px;
}

.dashboard-grid {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 20px;
}

.dashboard-main { display: flex; flex-direction: column; gap: 20px; }
.dashboard-side { display: flex; flex-direction: column; gap: 20px; }

/* ─── MODEL SET CARDS ───────────────────────────────────── */
.modelset-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}

.modelset-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  display: block;
  position: relative;
  overflow: hidden;
}
.modelset-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}
.modelset-card:hover { border-color: var(--primary-border); box-shadow: var(--shadow-md); transform: translateY(-2px); }
.modelset-card:hover::before { transform: scaleX(1); }

.modelset-top { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 12px; }
.modelset-icon { font-size: 1.75rem; }
.modelset-badges { display: flex; gap: 6px; flex-wrap: wrap; }

.modelset-title { font-size: 1rem; font-weight: 700; color: var(--text-primary); margin-bottom: 6px; line-height: 1.3; }
.modelset-desc { font-size: 0.8375rem; color: var(--text-muted); line-height: 1.5; margin-bottom: 16px; }

.modelset-meta {
  display: flex;
  gap: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--border);
}
.meta-item { display: flex; align-items: center; gap: 5px; font-size: 0.8rem; color: var(--text-secondary); }
.meta-icon { width: 14px; opacity: 0.7; }

/* Category Cards */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.category-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px 20px;
  text-decoration: none;
  display: block;
  transition: all var(--transition);
  cursor: pointer;
}
.category-card:hover { border-color: var(--primary-border); box-shadow: var(--shadow-md); transform: translateY(-2px); }

.category-icon-wrap {
  width: 56px; height: 56px;
  border-radius: var(--radius-lg);
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin-bottom: 14px;
}
.category-name { font-size: 1rem; font-weight: 700; margin-bottom: 6px; }
.category-desc { font-size: 0.8125rem; color: var(--text-muted); margin-bottom: 14px; }
.category-count { font-size: 0.8rem; color: var(--primary); font-weight: 600; }

/* ─── TEST INTERFACE ────────────────────────────────────── */
.test-layout {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 0;
  min-height: 100vh;
  background: var(--bg);
}

.test-topbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 60px;
  background: white;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.test-name { font-size: 0.9rem; font-weight: 700; color: var(--text-primary); }
.test-progress { font-size: 0.8rem; color: var(--text-muted); margin-top: 2px; }

.test-timer {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 8px 16px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  transition: all var(--transition);
}
.test-timer.warning { color: var(--warning); background: var(--warning-light); border-color: var(--warning); }
.test-timer.danger  { color: var(--danger); background: var(--danger-light); border-color: var(--danger); animation: timerPulse 1s infinite; }

@keyframes timerPulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.02); }
}

.test-main {
  margin-top: 60px;
  padding: 28px;
  max-width: 800px;
}

.test-sidebar-panel {
  width: 280px;
  position: fixed;
  right: 0;
  top: 60px;
  bottom: 0;
  background: white;
  border-left: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.test-sidebar-header {
  padding: 16px 18px;
  border-bottom: 1px solid var(--border);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.question-navigator {
  padding: 16px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.q-nav-btn {
  width: 38px; height: 38px;
  border-radius: var(--radius-md);
  border: 1.5px solid var(--border);
  background: white;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}
.q-nav-btn:hover { border-color: var(--primary); color: var(--primary); }
.q-nav-btn.current { border-color: var(--primary); background: var(--primary); color: white; }
.q-nav-btn.answered { border-color: var(--success); background: var(--success-light); color: var(--success); }
.q-nav-btn.marked { border-color: var(--warning); background: var(--warning-light); color: var(--warning); }
.q-nav-btn.answered.marked { border-color: var(--warning); background: var(--warning-light); }
.q-nav-btn.visited { border-color: var(--border-strong); background: var(--bg-subtle); }

.nav-legend {
  padding: 12px 16px;
  border-top: 1px solid var(--border);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}
.legend-item { display: flex; align-items: center; gap: 6px; font-size: 0.75rem; color: var(--text-secondary); }
.legend-dot {
  width: 14px; height: 14px;
  border-radius: 4px;
  border: 1.5px solid;
  flex-shrink: 0;
}
.legend-dot.not-visited { border-color: var(--border); background: white; }
.legend-dot.visited-d { border-color: var(--border-strong); background: var(--bg-subtle); }
.legend-dot.answered-d { border-color: var(--success); background: var(--success-light); }
.legend-dot.marked-d { border-color: var(--warning); background: var(--warning-light); }

.test-actions {
  padding: 16px;
  border-top: 1px solid var(--border);
  margin-top: auto;
}

/* Question Card */
.question-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-bottom: 20px;
  box-shadow: var(--shadow-sm);
}

.question-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}
.question-num {
  background: var(--primary);
  color: white;
  width: 32px; height: 32px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.875rem;
  font-weight: 700;
  flex-shrink: 0;
}
.question-meta { display: flex; gap: 8px; }

.question-text {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-primary);
  line-height: 1.65;
  margin-bottom: 22px;
}

.options-list { display: flex; flex-direction: column; gap: 10px; }

.option-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition);
  position: relative;
}
.option-item:hover { border-color: var(--primary-border); background: var(--primary-light); }
.option-item.selected { border-color: var(--primary); background: var(--primary-light); }
.option-item.correct { border-color: var(--success); background: var(--success-light); }
.option-item.incorrect { border-color: var(--danger); background: var(--danger-light); }

.option-item input[type="radio"] { display: none; }

.option-label {
  width: 30px; height: 30px;
  border-radius: 50%;
  border: 2px solid var(--border-strong);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--text-secondary);
  flex-shrink: 0;
  transition: all var(--transition);
}
.option-item.selected .option-label { border-color: var(--primary); background: var(--primary); color: white; }
.option-item.correct .option-label { border-color: var(--success); background: var(--success); color: white; }
.option-item.incorrect .option-label { border-color: var(--danger); background: var(--danger); color: white; }

.option-text { font-size: 0.9rem; color: var(--text-primary); line-height: 1.5; }

.question-nav-buttons {
  display: flex;
  gap: 10px;
  margin-top: 20px;
  flex-wrap: wrap;
}

/* ─── RESULTS PAGE ──────────────────────────────────────── */
.result-hero {
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  padding: 48px 24px;
  text-align: center;
  color: white;
}

.score-ring-wrap { display: flex; justify-content: center; margin-bottom: 24px; }

.score-ring {
  position: relative;
  width: 160px; height: 160px;
}
.score-ring svg { transform: rotate(-90deg); }
.score-ring-bg { fill: none; stroke: rgba(255,255,255,0.2); stroke-width: 8; }
.score-ring-fill { fill: none; stroke: white; stroke-width: 8; stroke-linecap: round; transition: stroke-dashoffset 1.5s ease; }
.score-ring-text {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: white;
}
.score-pct { font-size: 2.2rem; font-weight: 800; font-family: 'JetBrains Mono', monospace; line-height: 1; }
.score-label { font-size: 0.75rem; opacity: 0.8; margin-top: 4px; }

.result-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  max-width: 700px;
  margin: 0 auto;
}
.result-stat { background: rgba(255,255,255,0.15); border-radius: var(--radius-md); padding: 14px 10px; text-align: center; }
.result-stat-val { font-size: 1.5rem; font-weight: 800; display: block; font-family: 'JetBrains Mono', monospace; }
.result-stat-label { font-size: 0.75rem; opacity: 0.8; margin-top: 2px; }

.result-body { max-width: 900px; margin: 0 auto; padding: 32px 24px; }

.result-summary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 32px;
}

/* Answer Review */
.review-item {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  margin-bottom: 14px;
}
.review-item.correct { border-left: 4px solid var(--success); }
.review-item.incorrect { border-left: 4px solid var(--danger); }
.review-item.unattempted { border-left: 4px solid var(--text-muted); }

.review-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.review-qnum { font-size: 0.8rem; font-weight: 600; color: var(--text-muted); }
.review-status { display: flex; align-items: center; gap: 5px; font-size: 0.8125rem; font-weight: 700; }
.review-status.correct { color: var(--success); }
.review-status.incorrect { color: var(--danger); }
.review-status.unattempted { color: var(--text-muted); }

.review-question { font-size: 0.9rem; font-weight: 500; color: var(--text-primary); margin-bottom: 14px; line-height: 1.55; }

.review-options { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-bottom: 14px; }
.review-option {
  padding: 8px 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  display: flex;
  gap: 8px;
}
.review-option .opt-key { font-weight: 700; min-width: 20px; }
.review-option.correct-opt { background: var(--success-light); border-color: var(--success); color: var(--success); }
.review-option.user-wrong { background: var(--danger-light); border-color: var(--danger); color: var(--danger); }

.review-explanation {
  background: var(--accent-light);
  border: 1px solid #BAE6FD;
  border-radius: var(--radius-md);
  padding: 12px 14px;
  font-size: 0.8375rem;
  color: var(--info);
  line-height: 1.55;
}
.review-explanation strong { color: var(--info); }

/* ─── ADMIN PANEL ───────────────────────────────────────── */
.admin-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
}
.admin-table th {
  padding: 12px 16px;
  text-align: left;
  font-size: 0.775rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
  background: var(--bg-subtle);
}
.admin-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
  color: var(--text-primary);
  vertical-align: middle;
}
.admin-table tbody tr:hover { background: var(--bg-hover); }
.admin-table tbody tr:last-child td { border-bottom: none; }

.table-actions { display: flex; gap: 6px; justify-content: flex-end; }

.search-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  background: white;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  padding: 0 14px;
  transition: border-color var(--transition);
}
.search-bar:focus-within { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,0.1); }
.search-bar input { border: none; outline: none; padding: 10px 0; font-size: 0.875rem; flex: 1; background: transparent; }
.search-icon { color: var(--text-muted); flex-shrink: 0; }

.filter-row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }

/* Modal */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  backdrop-filter: blur(4px);
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
}
.modal-backdrop.open { opacity: 1; visibility: visible; }

.modal {
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  width: 100%;
  max-width: 620px;
  max-height: 90vh;
  overflow-y: auto;
  transform: translateY(20px) scale(0.98);
  transition: transform var(--transition);
}
.modal-backdrop.open .modal { transform: translateY(0) scale(1); }
.modal-lg { max-width: 860px; }

.modal-header { display: flex; justify-content: space-between; align-items: center; padding: 20px 24px; border-bottom: 1px solid var(--border); }
.modal-title { font-size: 1.05rem; font-weight: 700; }
.modal-close { background: none; border: none; color: var(--text-muted); cursor: pointer; padding: 4px; border-radius: var(--radius-md); transition: all var(--transition); font-size: 1.2rem; }
.modal-close:hover { background: var(--bg-subtle); color: var(--text-primary); }
.modal-body { padding: 24px; }
.modal-footer { padding: 16px 24px; border-top: 1px solid var(--border); display: flex; justify-content: flex-end; gap: 10px; }

/* ─── PROFILE ───────────────────────────────────────────── */
.profile-header {
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  border-radius: var(--radius-xl);
  padding: 32px;
  color: white;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.profile-avatar {
  width: 80px; height: 80px;
  border-radius: 50%;
  border: 4px solid rgba(255,255,255,0.4);
  object-fit: cover;
  background: rgba(255,255,255,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  font-weight: 700;
  flex-shrink: 0;
}
.profile-avatar img { width: 100%; height: 100%; border-radius: 50%; object-fit: cover; }
.profile-name { font-size: 1.5rem; font-weight: 800; margin-bottom: 4px; }
.profile-email { opacity: 0.8; font-size: 0.875rem; }
.profile-since { opacity: 0.7; font-size: 0.8rem; margin-top: 6px; }

/* Progress Bar */
.progress-bar-wrap { background: var(--bg-subtle); border-radius: var(--radius-full); height: 8px; overflow: hidden; }
.progress-bar-fill { height: 100%; border-radius: var(--radius-full); background: linear-gradient(90deg, var(--primary), var(--accent)); transition: width 1s ease; }

/* ─── EMPTY STATES ──────────────────────────────────────── */
.empty-state {
  text-align: center;
  padding: 60px 24px;
  color: var(--text-muted);
}
.empty-icon { font-size: 3rem; margin-bottom: 16px; opacity: 0.6; }
.empty-title { font-size: 1rem; font-weight: 700; color: var(--text-secondary); margin-bottom: 8px; }
.empty-desc { font-size: 0.875rem; line-height: 1.6; max-width: 360px; margin: 0 auto 20px; }

/* ─── LOADING STATES ────────────────────────────────────── */
.skeleton {
  background: linear-gradient(90deg, var(--bg-subtle) 25%, var(--border) 50%, var(--bg-subtle) 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.4s infinite;
  border-radius: var(--radius-md);
}
@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.loading-spinner {
  width: 20px; height: 20px;
  border: 2.5px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.page-loader {
  position: fixed;
  inset: 0;
  background: white;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  flex-direction: column;
  gap: 16px;
}
.page-loader .logo { width: 48px; height: 48px; background: linear-gradient(135deg, var(--primary), var(--accent)); border-radius: var(--radius-lg); display: flex; align-items: center; justify-content: center; color: white; font-weight: 800; font-size: 1.2rem; }
.page-loader .loading-spinner { width: 32px; height: 32px; }

/* ─── TOAST NOTIFICATIONS ───────────────────────────────── */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.toast {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: var(--shadow-xl);
  min-width: 280px;
  max-width: 400px;
  animation: toastIn 0.3s ease;
}
@keyframes toastIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
.toast.success { border-left: 4px solid var(--success); }
.toast.error   { border-left: 4px solid var(--danger); }
.toast.info    { border-left: 4px solid var(--primary); }
.toast-icon { font-size: 1.25rem; flex-shrink: 0; }
.toast-msg { font-size: 0.875rem; font-weight: 500; color: var(--text-primary); flex: 1; }

/* ─── SECTION HEADERS ────────────────────────────────────── */
.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}
.section-head-title { font-size: 1rem; font-weight: 700; color: var(--text-primary); }
.section-head-sub { font-size: 0.8125rem; color: var(--text-muted); margin-top: 2px; }

/* ─── LANDING PAGE ───────────────────────────────────────── */
.landing-hero {
  padding: calc(var(--topbar-h) + 80px) 24px 80px;
  text-align: center;
  background: linear-gradient(180deg, var(--primary-light) 0%, white 60%);
  border-bottom: 1px solid var(--border);
}
.landing-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--primary-light);
  color: var(--primary);
  border: 1px solid var(--primary-border);
  border-radius: var(--radius-full);
  padding: 5px 14px;
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 24px;
}
.landing-badge .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--success); animation: pulse 2s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; transform: scale(1); } 50% { opacity: 0.6; transform: scale(0.8); } }

.landing-title {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.15;
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}
.landing-title span { color: var(--primary); }

.landing-sub {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 540px;
  margin: 0 auto 36px;
  line-height: 1.75;
}

.landing-cta { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

.landing-trust {
  margin-top: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
}
.trust-item { display: flex; flex-direction: column; align-items: center; gap: 4px; }
.trust-num { font-size: 1.6rem; font-weight: 800; color: var(--primary); font-family: 'JetBrains Mono', monospace; }
.trust-label { font-size: 0.8rem; color: var(--text-muted); }

.features-section { padding: 80px 24px; }
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: box-shadow var(--transition);
}
.feature-card:hover { box-shadow: var(--shadow-md); }
.feature-icon { width: 48px; height: 48px; border-radius: var(--radius-md); background: var(--primary-light); display: flex; align-items: center; justify-content: center; font-size: 1.4rem; margin-bottom: 14px; }
.feature-title { font-size: 0.95rem; font-weight: 700; margin-bottom: 8px; }
.feature-desc { font-size: 0.8375rem; color: var(--text-muted); line-height: 1.6; }

/* ─── LOGIN PAGE ────────────────────────────────────────── */
.login-page {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 480px;
}
.login-left {
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  padding: 60px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  color: white;
}
.login-left-title { font-size: 2.5rem; font-weight: 800; color: white; margin-bottom: 16px; line-height: 1.2; }
.login-left-sub { font-size: 1rem; opacity: 0.85; line-height: 1.75; margin-bottom: 40px; }
.login-features { display: flex; flex-direction: column; gap: 14px; }
.login-feature { display: flex; align-items: center; gap: 12px; font-size: 0.9rem; opacity: 0.9; }
.login-feature-icon { width: 34px; height: 34px; background: rgba(255,255,255,0.15); border-radius: var(--radius-md); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }

.login-right {
  background: white;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 60px 48px;
}
.login-box { width: 100%; max-width: 380px; }
.login-logo { display: flex; align-items: center; gap: 10px; margin-bottom: 36px; }
.login-logo-icon { width: 44px; height: 44px; background: linear-gradient(135deg, var(--primary), var(--accent)); border-radius: var(--radius-lg); display: flex; align-items: center; justify-content: center; color: white; font-weight: 800; font-size: 1.1rem; }
.login-logo-name { font-size: 1.2rem; font-weight: 800; color: var(--text-primary); }

.login-title { font-size: 1.6rem; font-weight: 800; margin-bottom: 8px; }
.login-sub { font-size: 0.875rem; color: var(--text-muted); margin-bottom: 32px; line-height: 1.5; }

.login-divider { display: flex; align-items: center; gap: 14px; margin: 24px 0; }
.login-divider::before, .login-divider::after { content: ''; flex: 1; height: 1px; background: var(--border); }
.login-divider span { font-size: 0.8rem; color: var(--text-muted); white-space: nowrap; }

.login-footer { font-size: 0.775rem; color: var(--text-muted); text-align: center; margin-top: 24px; line-height: 1.6; }
.login-footer a { color: var(--primary); }

/* ─── INSTRUCTION PAGE ─────────────────────────────────── */
.instruction-page { max-width: 700px; margin: 0 auto; padding: 40px 24px; }
.instruction-card { background: white; border: 1px solid var(--border); border-radius: var(--radius-xl); overflow: hidden; box-shadow: var(--shadow-md); }
.instruction-header { background: linear-gradient(135deg, var(--primary), var(--accent)); padding: 28px 32px; color: white; }
.instruction-body { padding: 32px; }
.instruction-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 24px; }
.instr-stat { background: var(--bg-subtle); border-radius: var(--radius-md); padding: 14px 16px; }
.instr-stat-val { font-size: 1.3rem; font-weight: 800; color: var(--primary); font-family: 'JetBrains Mono', monospace; }
.instr-stat-label { font-size: 0.8rem; color: var(--text-muted); }
.instr-list { display: flex; flex-direction: column; gap: 10px; margin-bottom: 28px; }
.instr-item { display: flex; gap: 12px; align-items: flex-start; font-size: 0.875rem; color: var(--text-secondary); }
.instr-bullet { width: 24px; height: 24px; border-radius: 50%; background: var(--primary-light); color: var(--primary); display: flex; align-items: center; justify-content: center; font-size: 0.75rem; font-weight: 700; flex-shrink: 0; }

/* ─── RESPONSIVE ────────────────────────────────────────── */
@media (max-width: 1024px) {
  :root { --sidebar-w: 240px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .dashboard-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); }
  .sidebar.mobile-open { transform: translateX(0); }
  .main-content { margin-left: 0; }

  .test-layout { grid-template-columns: 1fr; }
  .test-sidebar-panel { position: fixed; bottom: 0; left: 0; right: 0; top: auto; width: 100%; max-height: 50vh; border-top: 1px solid var(--border); border-left: none; z-index: 50; transform: translateY(100%); transition: transform var(--transition-slow); }
  .test-sidebar-panel.mobile-open { transform: translateY(0); }

  .login-page { grid-template-columns: 1fr; }
  .login-left { display: none; }
  .login-right { padding: 40px 24px; }

  .result-stats { grid-template-columns: repeat(2, 1fr); }
  .result-summary-grid { grid-template-columns: 1fr 1fr; }
  .review-options { grid-template-columns: 1fr; }

  .stats-grid { grid-template-columns: 1fr 1fr; }
  .modelset-grid { grid-template-columns: 1fr; }
  .instruction-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .category-grid { grid-template-columns: 1fr 1fr; }

  .welcome-banner { flex-direction: column; gap: 20px; text-align: center; }
  .landing-hero { padding: calc(var(--topbar-h) + 40px) 16px 48px; }
}

@media (max-width: 480px) {
  .stats-grid { grid-template-columns: 1fr; }
  .category-grid { grid-template-columns: 1fr; }
  .topnav-links { display: none; }
  .test-timer { font-size: 1rem; padding: 6px 12px; }
  .question-card { padding: 18px; }
  .option-item { padding: 12px 14px; }
  .result-stats { grid-template-columns: repeat(2, 1fr); }
}

/* ─── PRINT STYLES ──────────────────────────────────────── */
@media print {
  .sidebar, .test-sidebar-panel, .test-topbar, .page-topbar, .toast-container { display: none !important; }
  .main-content { margin-left: 0; }
}