/* ============================================================
   StudyNexAcademy — Main Design System
   Version 2.0
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500&display=swap');

/* ============================================================
   CSS VARIABLES — DARK MODE (default)
   ============================================================ */
/* ============================================================
   CSS VARIABLES — LIGHT MODE (DEFAULT) & DARK NAVY MODE
   ============================================================ */
:root {
  /* Colors */
  --primary: #6c63ff;
  --primary-dark: #5a52d5;
  --primary-light: #818cf8;
  --primary-glow: rgba(108, 99, 255, 0.18);
  --accent: #f59e0b;
  --accent-dark: #d97706;
  --success: #10b981;
  --success-light: rgba(16, 185, 129, 0.12);
  --danger: #ef4444;
  --danger-light: rgba(239, 68, 68, 0.12);
  --warning: #f59e0b;
  --warning-light: rgba(245, 158, 11, 0.12);
  --info: #3b82f6;
  --info-light: rgba(59, 130, 246, 0.12);

  /* Light Mode Backgrounds (Soft Slate-Blue Canvas - Eliminates Glaring Flat White) */
  --bg-base: #f4f6fb;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f8fafc;
  --bg-elevated: #e9eef5;
  --bg-overlay: rgba(244, 246, 251, 0.94);

  /* Glass */
  --glass-bg: rgba(255, 255, 255, 0.90);
  --glass-border: rgba(15, 23, 42, 0.08);
  --glass-hover: rgba(15, 23, 42, 0.04);

  /* Light Text - High Contrast Deep Slate */
  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  --text-faint: #94a3b8;
  --text-inverse: #ffffff;

  /* Border */
  --border: #e2e8f0;
  --border-strong: #cbd5e1;

  /* Sidebar */
  --sidebar-bg: #ffffff;
  --sidebar-width: 280px;
  --sidebar-item-hover: rgba(108, 99, 255, 0.07);
  --sidebar-item-active: rgba(108, 99, 255, 0.13);

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.05), 0 1px 2px rgba(15, 23, 42, 0.03);
  --shadow-md: 0 4px 14px rgba(15, 23, 42, 0.07), 0 2px 4px rgba(15, 23, 42, 0.03);
  --shadow-lg: 0 10px 25px -3px rgba(15, 23, 42, 0.09), 0 4px 6px -2px rgba(15, 23, 42, 0.04);
  --shadow-xl: 0 20px 35px -5px rgba(15, 23, 42, 0.12);
  --shadow-glow: 0 0 25px var(--primary-glow);

  /* Code blocks */
  --code-bg: #f1f5f9;
  --code-border: #e2e8f0;
  --code-color: #5b21b6;
  --pre-bg: #0f172a;
  --pre-text: #f8fafc;

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

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --radius-full: 9999px;

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

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

/* ============================================================
   LIGHT MODE SPECIFIC OVERRIDES
   ============================================================ */
[data-theme="light"] {
  --bg-base: #f4f6fb;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f8fafc;
  --bg-elevated: #e9eef5;
  --bg-overlay: rgba(244, 246, 251, 0.94);

  --glass-bg: rgba(255, 255, 255, 0.90);
  --glass-border: rgba(15, 23, 42, 0.08);
  --glass-hover: rgba(15, 23, 42, 0.04);

  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  --text-faint: #94a3b8;
  --text-inverse: #ffffff;

  --border: #e2e8f0;
  --border-strong: #cbd5e1;

  --sidebar-bg: #ffffff;
  --sidebar-item-hover: rgba(108, 99, 255, 0.07);
  --sidebar-item-active: rgba(108, 99, 255, 0.13);

  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.05), 0 1px 2px rgba(15, 23, 42, 0.03);
  --shadow-md: 0 4px 14px rgba(15, 23, 42, 0.07), 0 2px 4px rgba(15, 23, 42, 0.03);
  --shadow-lg: 0 10px 25px -3px rgba(15, 23, 42, 0.09), 0 4px 6px -2px rgba(15, 23, 42, 0.04);
  --shadow-xl: 0 20px 35px -5px rgba(15, 23, 42, 0.12);

  --code-bg: #f1f5f9;
  --code-border: #e2e8f0;
  --code-color: #5b21b6;
  --pre-bg: #0f172a;
  --pre-text: #f8fafc;
}

/* ============================================================
   DARK NAVY MODE
   ============================================================ */
[data-theme="dark"] {
  /* Refined Professional Dark Navy Palette */
  --bg-base: #0b1329;
  --bg-surface: #121d3a;
  --bg-card: #172447;
  --bg-card-hover: #1e2f5b;
  --bg-elevated: #223566;
  --bg-overlay: rgba(11, 19, 41, 0.88);

  --glass-bg: rgba(23, 36, 71, 0.75);
  --glass-border: rgba(255, 255, 255, 0.09);
  --glass-hover: rgba(255, 255, 255, 0.04);

  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-faint: #475569;
  --text-inverse: #0b1329;

  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.18);

  --sidebar-bg: #0f1731;
  --sidebar-item-hover: rgba(108, 99, 255, 0.12);
  --sidebar-item-active: rgba(108, 99, 255, 0.22);

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.55);
  --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.65);

  --code-bg: #121d3a;
  --code-border: rgba(255, 255, 255, 0.1);
  --code-color: #a78bfa;
  --pre-bg: #0b1329;
  --pre-text: #f8fafc;
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  transition: background-color 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}

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

a:hover { color: var(--primary-light); }

img { max-width: 100%; height: auto; display: block; }

ul, ol { list-style: none; }

button { cursor: pointer; border: none; background: none; font-family: var(--font-sans); }

input, textarea, select {
  font-family: var(--font-sans);
  font-size: 1rem;
}

::selection {
  background: var(--primary);
  color: white;
}

:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ============================================================
   SCROLLBAR
   ============================================================ */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg-surface); }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--primary); }

/* ============================================================
   TYPOGRAPHY
   ============================================================ */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
}

h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); }
h3 { font-size: clamp(1.1rem, 2.5vw, 1.5rem); }
h4 { font-size: 1.15rem; }
h5 { font-size: 1rem; }

p { margin-bottom: 1rem; color: var(--text-secondary); }

.text-primary { color: var(--primary) !important; }
.text-accent { color: var(--accent) !important; }
.text-muted { color: var(--text-muted) !important; }
.text-success { color: var(--success) !important; }
.text-danger { color: var(--danger) !important; }
.text-warning { color: var(--warning) !important; }
.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }
.text-lg { font-size: 1.125rem; }
.text-xl { font-size: 1.25rem; }
.text-2xl { font-size: 1.5rem; }
.text-3xl { font-size: 1.875rem; }
.font-bold { font-weight: 700; }
.font-semibold { font-weight: 600; }
.font-medium { font-weight: 500; }

/* ============================================================
   LAYOUT
   ============================================================ */
.container {
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 1.5rem;
  box-sizing: border-box;
}

.container-sm { max-width: 860px; }
.container-lg { max-width: 1560px; }

.section { padding: 5rem 0; }
.section-sm { padding: 3rem 0; }

.grid { display: grid; }
.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }
.gap-4 { gap: 2rem; }
.w-full { width: 100%; }
.h-full { height: 100%; }

/* Three-column tutorial layout */
.layout-three-col {
  display: grid;
  grid-template-columns: var(--sidebar-width) 1fr 280px;
  gap: 0;
  min-height: calc(100vh - 70px);
  min-width: 0;
  /* Paint sidebar background across the entire left column height */
  background: linear-gradient(
    to right,
    var(--sidebar-bg) var(--sidebar-width),
    transparent var(--sidebar-width)
  );
}
.layout-three-col > * { min-width: 0; }

/* ============================================================
   NAVBAR
   ============================================================ */
.navbar {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--glass-border);
  height: 70px;
  display: flex;
  align-items: center;
  overflow: visible;
  transition: height 0.3s cubic-bezier(0.4, 0, 0.2, 1), background 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.navbar.scrolled {
  height: 60px;
  background: var(--bg-surface);
  box-shadow: var(--shadow-md);
  border-bottom-color: var(--border);
}

.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 1.5rem;
  min-width: 0;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

.navbar-logo {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 1rem;
  color: white;
  box-shadow: var(--shadow-glow);
}

.navbar-brand-name {
  font-size: 1.15rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary-light), #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex: 1;
}

.nav-link {
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background: var(--primary-glow);
}

.navbar-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
  min-width: 0;
}

.search-trigger {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 0.85rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  color: var(--text-muted);
  font-size: 0.85rem;
  cursor: pointer;
  transition: var(--transition);
  min-width: 180px;
}

.search-trigger:hover {
  border-color: var(--primary);
  color: var(--text-primary);
}

.search-trigger kbd {
  margin-left: auto;
  padding: 0.1rem 0.4rem;
  background: var(--bg-card);
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  font-size: 0.7rem;
  font-family: var(--font-mono);
}

.theme-toggle {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  cursor: pointer;
  position: relative;
  z-index: 10;
}

.theme-toggle:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--primary-glow);
}

.hamburger {
  display: none;
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text-secondary);
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

/* Mobile Nav Drawer */
.mobile-nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: var(--z-overlay);
  visibility: hidden;
  opacity: 0;
  transition: var(--transition-slow);
}

.mobile-nav.open {
  visibility: visible;
  opacity: 1;
}

.mobile-nav-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(4px);
}

.mobile-nav-drawer {
  position: absolute;
  top: 0;
  right: -320px;
  width: 300px;
  height: 100%;
  background: var(--bg-surface);
  border-left: 1px solid var(--border);
  padding: 2rem 1.5rem;
  overflow-y: auto;
  transition: right 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.mobile-nav.open .mobile-nav-drawer {
  right: 0;
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-top: 2rem;
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-md);
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
}

.mobile-nav-link:hover {
  background: var(--primary-glow);
  color: var(--primary);
}

/* ============================================================
   SEARCH OVERLAY
   ============================================================ */
.search-overlay {
  position: fixed;
  inset: 0;
  z-index: var(--z-modal);
  background: var(--bg-overlay);
  backdrop-filter: blur(20px);
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 10vh;
  visibility: hidden;
  opacity: 0;
  transition: var(--transition);
}

.search-overlay.open {
  visibility: visible;
  opacity: 1;
}

.search-box {
  width: 100%;
  max-width: 640px;
  background: var(--bg-card);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  transform: translateY(-20px) scale(0.98);
  transition: transform 0.3s ease;
}

.search-overlay.open .search-box {
  transform: translateY(0) scale(1);
}

.search-input-wrap {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border);
}

.search-input-wrap svg { color: var(--text-muted); flex-shrink: 0; }

.search-input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  font-size: 1.15rem;
  color: var(--text-primary);
}

.search-input::placeholder { color: var(--text-muted); }

.search-results {
  max-height: 400px;
  overflow-y: auto;
  padding: 0.75rem;
}

.search-result-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.75rem;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: var(--transition);
}

.search-result-item:hover {
  background: var(--bg-elevated);
}

.search-hint {
  padding: 1rem 1.5rem;
  color: var(--text-muted);
  font-size: 0.85rem;
  text-align: center;
}

/* ============================================================
   HERO SECTION
   ============================================================ */
.hero {
  position: relative;
  padding: 5rem 0 6rem;
  overflow: hidden;
  background: radial-gradient(ellipse at 20% 50%, rgba(108,99,255,0.12) 0%, transparent 60%),
              radial-gradient(ellipse at 80% 20%, rgba(167,139,250,0.08) 0%, transparent 50%),
              var(--bg-base);
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%236c63ff' fill-opacity='0.03'%3E%3Ccircle cx='30' cy='30' r='2'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  pointer-events: none;
}

.hero-content {
  position: relative;
  text-align: center;
  max-width: 780px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  background: var(--primary-glow);
  border: 1px solid rgba(108,99,255,0.3);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary-light);
  margin-bottom: 1.5rem;
  animation: fadeInDown 0.6s ease;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 900;
  line-height: 1.1;
  margin-bottom: 1.5rem;
  animation: fadeInUp 0.6s ease 0.1s both;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, var(--primary-light), #a78bfa, var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-bottom: 3rem;
  animation: fadeInUp 0.6s ease 0.2s both;
}

/* Dual Path Cards */
.hero-paths {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  max-width: 700px;
  margin: 0 auto 3rem;
  animation: fadeInUp 0.6s ease 0.3s both;
}

.path-card {
  position: relative;
  padding: 2rem 1.5rem;
  border-radius: var(--radius-xl);
  border: 1px solid var(--border);
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  text-align: left;
  cursor: pointer;
  transition: var(--transition-slow);
  overflow: hidden;
  text-decoration: none;
}

.path-card::before {
  content: '';
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 0.4s ease;
  border-radius: var(--radius-xl);
}

.path-card-learn::before {
  background: linear-gradient(135deg, rgba(108,99,255,0.15), rgba(167,139,250,0.08));
}

.path-card-practice::before {
  background: linear-gradient(135deg, rgba(245,158,11,0.15), rgba(251,191,36,0.08));
}

.path-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-xl); }
.path-card:hover::before { opacity: 1; }
.path-card:hover { border-color: var(--primary); }
.path-card-practice:hover { border-color: var(--accent); }

.path-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
}

.path-icon-learn { background: var(--primary-glow); color: var(--primary); }
.path-icon-practice { background: rgba(245,158,11,0.15); color: var(--accent); }

.path-label {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.4rem;
}

.path-title { font-size: 1.2rem; font-weight: 700; margin-bottom: 0.5rem; }
.path-desc { font-size: 0.85rem; color: var(--text-muted); margin: 0; }

.path-arrow {
  position: absolute;
  bottom: 1.5rem;
  right: 1.5rem;
  color: var(--text-muted);
  transition: var(--transition);
}

.path-card:hover .path-arrow { color: var(--primary); transform: translateX(4px); }
.path-card-practice:hover .path-arrow { color: var(--accent); }

/* Stats bar */
.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
  animation: fadeInUp 0.6s ease 0.4s both;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
}

.stat-value {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1;
}

.stat-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.stat-divider {
  width: 1px;
  height: 40px;
  background: var(--border);
}

/* ============================================================
   CARDS & GRID COMPONENTS
   ============================================================ */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.1rem 1.2rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease, background 0.22s ease;
}

.card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  box-shadow: var(--shadow-md);
  transform: translateY(-2.5px);
}

.card-glass {
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
}

/* ============================================================
   GLOBAL MODERN CARD DESIGN SYSTEM (SNA CARD COMPONENT)
   Compact, Modern, Dual-Tone Half-and-Half Accent Design
   ============================================================ */

/* 1. Responsive Card Grids (Applies to both new and existing live PHP pages) */
.sna-cards-grid,
.cards-grid-compact,
.grid-3,
div:has(> .subject-test-card),
div:has(> .test-item-card) {
  display: grid !important;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)) !important;
  gap: 1.15rem !important;
  width: 100%;
}

@media (min-width: 1280px) {
  .sna-cards-grid,
  .cards-grid-compact,
  .grid-3,
  div:has(> .subject-test-card),
  div:has(> .test-item-card) {
    grid-template-columns: repeat(auto-fill, minmax(270px, 1fr)) !important;
    gap: 1.25rem !important;
  }
}

@media (max-width: 640px) {
  .sna-cards-grid,
  .cards-grid-compact,
  .grid-3,
  div:has(> .subject-test-card),
  div:has(> .test-item-card) {
    grid-template-columns: 1fr !important;
    gap: 1rem !important;
  }
}

/* 2. Main SNA Card Component & Universal Overrides */
.sna-card,
.subject-test-card,
.subject-card,
.test-item-card {
  --c-accent: var(--card-color, var(--primary));
  position: relative;
  display: flex !important;
  flex-direction: column !important;
  justify-content: space-between !important;
  background: linear-gradient(180deg, 
    color-mix(in srgb, var(--c-accent, var(--primary)) 8%, var(--bg-card)) 0%, 
    color-mix(in srgb, var(--c-accent, var(--primary)) 1.5%, var(--bg-card)) 55%, 
    var(--bg-card) 100%) !important;
  border: 1px solid var(--border) !important;
  border-radius: var(--radius-lg) !important;
  padding: 1.1rem 1.2rem !important;
  overflow: hidden !important;
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow-sm);
  transition: transform 0.22s cubic-bezier(0.16, 1, 0.3, 1), 
              box-shadow 0.22s cubic-bezier(0.16, 1, 0.3, 1), 
              border-color 0.22s ease,
              background 0.22s ease !important;
  height: 100%;
}

[data-theme="dark"] .sna-card,
[data-theme="dark"] .subject-test-card,
[data-theme="dark"] .subject-card,
[data-theme="dark"] .test-item-card {
  background: linear-gradient(180deg, 
    color-mix(in srgb, var(--c-accent, var(--primary)) 18%, var(--bg-card)) 0%, 
    color-mix(in srgb, var(--c-accent, var(--primary)) 4%, var(--bg-card)) 65%, 
    var(--bg-card) 100%) !important;
}

/* Top Accent Stripe */
.sna-card::before,
.subject-test-card::before,
.subject-card::before,
.test-item-card::before {
  content: '' !important;
  position: absolute !important;
  top: 0 !important;
  left: 0 !important;
  right: 0 !important;
  height: 3.5px !important;
  background: var(--c-accent, var(--primary)) !important;
  z-index: 3 !important;
  transition: height 0.22s ease;
}

.sna-card:hover,
.subject-test-card:hover,
.subject-card:hover,
.test-item-card:hover {
  transform: translateY(-3.5px) !important;
  border-color: color-mix(in srgb, var(--c-accent, var(--primary)) 45%, var(--border)) !important;
  box-shadow: 0 10px 24px -5px color-mix(in srgb, var(--c-accent, var(--primary)) 22%, rgba(15, 23, 42, 0.08)),
              0 2px 6px rgba(0, 0, 0, 0.04) !important;
  color: inherit;
}

.sna-card:hover::before,
.subject-test-card:hover::before,
.subject-card:hover::before,
.test-item-card:hover::before {
  height: 4.5px !important;
}

/* 3. Half-and-Half Ambient Top Header */
.sna-card-header,
.test-item-header {
  position: relative;
  padding: 1rem 1.1rem 0.75rem;
  background: linear-gradient(180deg, 
    color-mix(in srgb, var(--c-accent) 12%, var(--bg-card)) 0%, 
    color-mix(in srgb, var(--c-accent) 3%, var(--bg-card)) 70%, 
    var(--bg-card) 100%);
  border-bottom: 1px solid color-mix(in srgb, var(--c-accent) 12%, var(--border));
  margin: -1.1rem -1.2rem 0.75rem -1.2rem;
}

[data-theme="dark"] .sna-card-header,
[data-theme="dark"] .test-item-header {
  background: linear-gradient(180deg, 
    color-mix(in srgb, var(--c-accent) 22%, var(--bg-card)) 0%, 
    color-mix(in srgb, var(--c-accent) 6%, var(--bg-card)) 80%, 
    var(--bg-card) 100%);
  border-bottom-color: color-mix(in srgb, var(--c-accent) 22%, var(--border));
}

.sna-card-top-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 0.65rem;
}

/* Glowing Icon Box (Target both class and inline style divs) */
.sna-card-icon,
.subject-icon,
.subject-test-card div[style*="width: 48px"],
.subject-test-card div[style*="width:48px"],
.subject-card div[style*="width: 38px"],
.subject-card div[style*="width:38px"] {
  width: 38px !important;
  height: 38px !important;
  min-width: 38px !important;
  border-radius: var(--radius-md) !important;
  display: flex !important;
  align-items: center !important;
  justify-content: center !important;
  flex-shrink: 0 !important;
  font-size: 1.15rem !important;
  background: color-mix(in srgb, var(--c-accent, var(--primary)) 15%, var(--bg-card)) !important;
  color: var(--c-accent, var(--primary)) !important;
  border: 1px solid color-mix(in srgb, var(--c-accent, var(--primary)) 28%, transparent) !important;
  box-shadow: 0 2px 6px color-mix(in srgb, var(--c-accent, var(--primary)) 16%, transparent) !important;
  transition: transform 0.22s ease, background 0.22s ease !important;
  margin: 0 !important;
}

.sna-card:hover .sna-card-icon,
.subject-card:hover .subject-icon,
.subject-test-card:hover .sna-card-icon,
.subject-test-card:hover div[style*="width: 48px"],
.subject-test-card:hover div[style*="width:48px"] {
  transform: scale(1.08) !important;
  background: color-mix(in srgb, var(--c-accent, var(--primary)) 25%, var(--bg-card)) !important;
}

/* Dynamic Badge */
.sna-card-badge,
.subject-test-card span.badge {
  display: inline-flex !important;
  align-items: center !important;
  gap: 0.25rem !important;
  font-size: 0.68rem !important;
  font-weight: 800 !important;
  letter-spacing: 0.03em !important;
  padding: 0.2rem 0.55rem !important;
  border-radius: var(--radius-full) !important;
  background: color-mix(in srgb, var(--c-accent, var(--primary)) 14%, var(--bg-card)) !important;
  color: var(--c-accent, var(--primary)) !important;
  border: 1px solid color-mix(in srgb, var(--c-accent, var(--primary)) 25%, transparent) !important;
  text-transform: uppercase !important;
  white-space: nowrap !important;
}

/* Card Title */
.sna-card-title,
.subject-name,
.subject-test-card h2,
.subject-test-card h3,
.subject-card h2,
.subject-card h3 {
  font-size: 1.02rem !important;
  font-weight: 700 !important;
  color: var(--text-primary) !important;
  line-height: 1.35 !important;
  margin: 0.25rem 0 0.35rem 0 !important;
  display: -webkit-box !important;
  -webkit-line-clamp: 2 !important;
  -webkit-box-orient: vertical !important;
  overflow: hidden !important;
  transition: color 0.2s ease;
}

.sna-card:hover .sna-card-title,
.subject-card:hover .subject-name,
.subject-test-card:hover .sna-card-title,
.subject-test-card:hover h2 {
  color: var(--c-accent, var(--primary)) !important;
}

/* 4. Card Body & Content */
.sna-card-body,
.test-item-body {
  padding: 0.25rem 0 0.5rem 0;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.sna-card-desc,
.subject-desc,
.subject-test-card p,
.subject-card p {
  font-size: 0.8rem !important;
  color: var(--text-muted) !important;
  line-height: 1.45 !important;
  min-height: unset !important;
  margin: 0 0 0.75rem 0 !important;
  display: -webkit-box !important;
  -webkit-line-clamp: 2 !important;
  -webkit-box-orient: vertical !important;
  overflow: hidden !important;
  flex: 1;
}

/* Chips / Details Pill Bar */
.sna-card-chips,
.subject-test-card div[style*="display: flex; gap: 0.6rem"],
.subject-test-card div[style*="display:flex;gap:.6rem"] {
  display: flex !important;
  gap: 0.4rem !important;
  flex-wrap: wrap !important;
  align-items: center !important;
  margin-top: auto !important;
  margin-bottom: 0.75rem !important;
}

.sna-chip,
.subject-test-card span[style*="background: var(--bg-surface)"],
.subject-test-card span[style*="background:var(--bg-surface)"] {
  display: inline-flex !important;
  align-items: center !important;
  gap: 0.28rem !important;
  padding: 0.22rem 0.5rem !important;
  border-radius: 6px !important;
  background: var(--bg-surface) !important;
  border: 1px solid var(--border) !important;
  color: var(--text-secondary) !important;
  font-size: 0.73rem !important;
  font-weight: 600 !important;
  line-height: 1.2 !important;
}

.sna-chip svg,
.subject-test-card span[style*="background: var(--bg-surface)"] svg {
  color: var(--c-accent, var(--primary)) !important;
}

/* 5. Card Footer & Actions */
.sna-card-footer,
.subject-footer,
.test-item-footer {
  padding-top: 0.65rem;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-top: auto;
}

.sna-card-action-link,
.btn-explore {
  font-size: 0.8rem !important;
  font-weight: 700 !important;
  color: var(--c-accent, var(--primary)) !important;
  display: inline-flex !important;
  align-items: center !important;
  gap: 0.25rem !important;
  margin-left: auto !important;
  transition: gap 0.2s ease, transform 0.2s ease;
  text-decoration: none !important;
}

.sna-card:hover .sna-card-action-link,
.subject-card:hover .btn-explore {
  gap: 0.45rem !important;
}

.sna-card-btn,
.subject-test-card a.btn-primary,
.test-item-card a.btn-primary {
  width: 100% !important;
  display: inline-flex !important;
  align-items: center !important;
  justify-content: center !important;
  gap: 0.4rem !important;
  padding: 0.48rem 0.85rem !important;
  border-radius: var(--radius-md) !important;
  font-size: 0.82rem !important;
  font-weight: 700 !important;
  background: var(--c-accent, var(--primary)) !important;
  color: #ffffff !important;
  border: none !important;
  cursor: pointer;
  box-shadow: 0 3px 8px color-mix(in srgb, var(--c-accent, var(--primary)) 30%, transparent) !important;
  transition: opacity 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease !important;
  text-decoration: none !important;
}

.sna-card-btn:hover,
.subject-test-card a.btn-primary:hover,
.test-item-card a.btn-primary:hover {
  transform: translateY(-1px) !important;
  box-shadow: 0 5px 14px color-mix(in srgb, var(--c-accent, var(--primary)) 45%, transparent) !important;
  opacity: 0.95 !important;
}

.sna-card-btn-disabled,
.subject-test-card button.btn-outline[disabled] {
  width: 100% !important;
  display: inline-flex !important;
  align-items: center !important;
  justify-content: center !important;
  padding: 0.48rem 0.85rem !important;
  border-radius: var(--radius-md) !important;
  font-size: 0.78rem !important;
  font-weight: 600 !important;
  background: var(--bg-surface) !important;
  border: 1px dashed var(--border-strong) !important;
  color: var(--text-muted) !important;
  cursor: not-allowed !important;
  user-select: none !important;
  opacity: 0.8 !important;
}

/* MCQ Category Card */
.mcq-cat-card {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding: 1rem 1.15rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

.mcq-cat-card:hover {
  border-color: var(--border-strong);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  color: inherit;
}

.mcq-cat-icon {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Blog Grid — responsive auto-fill */
.blog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(300px, 100%), 1fr));
  gap: 1.5rem;
  min-width: 0;
}
.blog-grid > * { min-width: 0; max-width: 100%; }

/* Blog Card */
.blog-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition-slow);
  display: flex;
  flex-direction: column;
  height: 100%;
  position: relative;
}

.blog-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  opacity: 0;
  transition: opacity 0.3s ease;
}

.blog-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border-strong);
}

.blog-card:hover::before { opacity: 1; }

.blog-card-image {
  aspect-ratio: 16/9;
  overflow: hidden;
  background: var(--bg-elevated);
  flex-shrink: 0;
}

.blog-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.blog-card:hover .blog-card-image img { transform: scale(1.07); }

.blog-card-body {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.blog-card-excerpt {
  font-size: 0.83rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  flex: 1;
}

.blog-card-category {
  display: inline-block;
  padding: 0.2rem 0.65rem;
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.75rem;
}

.blog-card-title {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 0.6rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.blog-card-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: auto;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
  flex-wrap: wrap;
}

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.9rem;
  transition: var(--transition);
  cursor: pointer;
  border: 1px solid transparent;
  text-decoration: none;
  white-space: nowrap;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
  border-color: var(--primary-dark);
  color: white;
  box-shadow: 0 0 20px var(--primary-glow);
  transform: translateY(-1px);
}

.btn-outline {
  background: transparent;
  color: var(--primary);
  border-color: var(--primary);
}

.btn-outline:hover {
  background: var(--primary);
  color: white;
}

.btn-ghost {
  background: var(--bg-elevated);
  color: var(--text-secondary);
  border-color: var(--border);
}

.btn-ghost:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  color: var(--text-primary);
}

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

.btn-sm { padding: 0.4rem 0.85rem; font-size: 0.82rem; min-height: 36px; }
.btn-lg { padding: 0.85rem 2rem; font-size: 1rem; }

.btn-icon {
  width: 36px;
  height: 36px;
  padding: 0;
  border-radius: var(--radius-md);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

/* ============================================================
   BADGES & PILLS
   ============================================================ */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.22rem 0.65rem;
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.badge-primary { background: var(--primary-glow); color: var(--primary); border: 1px solid rgba(108,99,255,0.28); }
.badge-success { background: var(--success-light); color: var(--success); border: 1px solid rgba(16,185,129,0.28); }
.badge-danger { background: var(--danger-light); color: var(--danger); border: 1px solid rgba(239,68,68,0.28); }
.badge-warning { background: var(--warning-light); color: var(--warning); border: 1px solid rgba(245,158,11,0.28); }
.badge-info { background: var(--info-light); color: var(--info); border: 1px solid rgba(59,130,246,0.28); }
.badge-secondary { background: var(--bg-elevated); color: var(--text-muted); border: 1px solid var(--border); }
.badge-subtle { background: var(--bg-surface); color: var(--text-secondary); border: 1px solid var(--border); }
.badge-subtle:hover { border-color: var(--primary); color: var(--primary); }

/* Category & Stream Pills Bar */
.filter-pills-bar {
  display: flex;
  gap: 0.55rem;
  align-items: center;
  flex-wrap: wrap;
  margin-bottom: 1.75rem;
  padding: 0.65rem 1rem;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

/* ============================================================
   PROFESSIONAL SECTION HEADERS
   ============================================================ */
.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 1.75rem;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.sec-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.3rem 0.8rem;
  border-radius: var(--radius-full);
  font-size: 0.74rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.45rem;
  box-shadow: 0 1px 2px rgba(0,0,0,0.03);
}

.sec-badge-indigo { background: rgba(108, 99, 255, 0.1); color: var(--primary); border: 1px solid rgba(108, 99, 255, 0.25); }
.sec-badge-emerald { background: rgba(16, 185, 129, 0.1); color: #10b981; border: 1px solid rgba(16, 185, 129, 0.25); }
.sec-badge-amber { background: rgba(245, 158, 11, 0.1); color: #d97706; border: 1px solid rgba(245, 158, 11, 0.25); }
.sec-badge-cyan { background: rgba(6, 182, 212, 0.1); color: #0891b2; border: 1px solid rgba(6, 182, 212, 0.25); }
.sec-badge-purple { background: rgba(168, 85, 247, 0.1); color: #9333ea; border: 1px solid rgba(168, 85, 247, 0.25); }
.sec-badge-rose { background: rgba(239, 68, 68, 0.1); color: #e11d48; border: 1px solid rgba(239, 68, 68, 0.25); }

.section-title {
  font-size: clamp(1.35rem, 2.8vw, 1.85rem);
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.25;
  letter-spacing: -0.015em;
  margin-bottom: 0.35rem;
}

.section-title span {
  color: var(--primary);
}

.section-subtitle {
  color: var(--text-muted);
  margin-top: 0.25rem;
  margin-bottom: 0;
  font-size: 0.88rem;
  line-height: 1.5;
}

.section-action-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.45rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 700;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  text-decoration: none;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
  white-space: nowrap;
}

.section-action-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--bg-card-hover);
  transform: translateY(-1px);
}

/* ============================================================
   TUTORIAL SIDEBAR (LEFT)
   ============================================================ */
.tutorial-sidebar {
  width: var(--sidebar-width);
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  /* Sticky within the grid column — height is viewport height */
  height: calc(100vh - 70px);
  position: sticky;
  top: 70px;
  overflow-y: auto;
  overflow-x: hidden;
  flex-shrink: 0;
  /* Ensure the grid column background shows below the sticky box */
  align-self: start;
}

.tutorial-sidebar::-webkit-scrollbar { width: 4px; }

.sidebar-subject-header {
  padding: 1.25rem 1rem;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: var(--sidebar-bg);
  z-index: 1;
}

.sidebar-subject-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.sidebar-subject-count {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.sidebar-chapter {
  border-bottom: 1px solid var(--border);
}

.sidebar-chapter-toggle {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: var(--transition);
  background: none;
  border: none;
}

.sidebar-chapter-toggle:hover { color: var(--text-primary); }

.sidebar-chapter-toggle .chapter-arrow {
  margin-left: auto;
  transition: transform 0.2s ease;
}

.sidebar-chapter.open .chapter-arrow { transform: rotate(90deg); }

.sidebar-topics { display: none; }
.sidebar-chapter.open .sidebar-topics { display: block; }

.sidebar-topic {
  display: flex;
  align-items: center;
  padding: 0.55rem 1rem 0.55rem 2rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  border-radius: 0;
  transition: var(--transition);
  text-decoration: none;
  border-left: 2px solid transparent;
}

.sidebar-topic:hover {
  color: var(--primary);
  background: var(--sidebar-item-hover);
  border-left-color: var(--primary);
}

.sidebar-topic.active {
  color: var(--primary);
  background: var(--sidebar-item-active);
  border-left-color: var(--primary);
  font-weight: 600;
}

/* ============================================================
   TUTORIAL CONTENT AREA
   ============================================================ */
.tutorial-content {
  padding: 3rem 4rem;
  min-width: 0;
  max-width: 920px;
  width: 100%;
  margin: 0 auto;
}

.tutorial-header {
  margin-bottom: 2.5rem;
  padding-bottom: 1.75rem;
  border-bottom: 1px solid var(--border);
}

.tutorial-title {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 1rem;
}

.tutorial-meta {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.tutorial-meta-item {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.tutorial-share {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: auto;
}

/* Tutorial prose content & long-form readability improvements */
.prose {
  font-size: 1.05rem;
  line-height: 1.85;
  color: var(--text-secondary);
  /* Prevent long words/URLs from overflowing on mobile */
  overflow-wrap: break-word;
  word-break: break-word;
  min-width: 0;
  max-width: 100%;
}

.prose p {
  margin-bottom: 1.5rem;
}

.prose h1, .prose h2, .prose h3, .prose h4, .prose h5, .prose h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.3;
  margin-top: 2.75rem;
  margin-bottom: 1.25rem;
}

.prose h1 {
  font-size: 2.2rem;
}

.prose h2 {
  font-size: 1.65rem;
  margin: 2.75rem 0 1.25rem;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--primary-glow);
}

.prose h3 {
  font-size: 1.3rem;
  margin: 2.25rem 0 1rem;
}

.prose h4 {
  font-size: 1.15rem;
  margin: 1.75rem 0 0.75rem;
}

.prose ul, .prose ol {
  margin: 1.25rem 0 1.5rem 1.75rem;
  padding-left: 0;
}

.prose ul {
  list-style-type: disc !important;
}

.prose ol {
  list-style-type: decimal !important;
}

.prose li {
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
  line-height: 1.75;
}

.prose li::marker {
  color: var(--primary);
  font-weight: 600;
}

.prose strong {
  color: var(--text-primary);
  font-weight: 700;
}

.prose code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--bg-elevated);
  padding: 0.18em 0.45em;
  border-radius: 4px;
  color: var(--primary-light);
  border: 1px solid var(--border);
  word-break: break-word;
  white-space: normal;
}

.prose pre {
  position: relative;
  background: #0d0d1a;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  overflow-x: auto;
  margin: 1.75rem 0;
  box-shadow: var(--shadow-sm);
}

.prose pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.9rem;
  color: #e2e8f0;
  word-break: normal;
  white-space: pre;
}

/* Dark-mode: high contrast prose readability */
[data-theme="dark"] .prose {
  color: #e2e8f0;
}
[data-theme="dark"] .prose p,
[data-theme="dark"] .prose li {
  color: #cbd5e1;
}
[data-theme="dark"] .prose h1,
[data-theme="dark"] .prose h2,
[data-theme="dark"] .prose h3,
[data-theme="dark"] .prose h4 {
  color: #f8fafc;
}
[data-theme="dark"] .prose strong {
  color: #ffffff;
}

/* Light-mode: readable code blocks */
[data-theme="light"] .prose pre {
  background: #f1f5f9;
  border-color: rgba(0,0,0,0.12);
  box-shadow: var(--shadow-sm), inset 0 1px 4px rgba(0,0,0,0.06);
}

[data-theme="light"] .prose pre code {
  color: #1e293b;
}

[data-theme="light"] .prose code {
  background: rgba(108, 99, 255, 0.08);
  color: #5b21b6;
  border-color: rgba(108, 99, 255, 0.2);
}

.copy-btn {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  padding: 0.3rem 0.65rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.72rem;
  color: var(--text-muted);
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 0.3rem;
  z-index: 10;
}

.copy-btn:hover { color: var(--primary); border-color: var(--primary); }
.copy-btn.copied { color: var(--success); border-color: var(--success); }

/* Blockquotes, horizontal lines, and images */
.prose blockquote {
  margin: 2rem 0;
  padding: 1rem 1.5rem;
  border-left: 4px solid var(--primary);
  background: var(--bg-elevated);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  color: var(--text-secondary);
  font-style: italic;
}

.prose blockquote p {
  margin-bottom: 0;
}

.prose hr {
  border: 0;
  height: 1px;
  background: var(--border-strong);
  margin: 2.5rem 0;
}

.prose img, .prose video, .prose iframe {
  margin: 2rem 0;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  max-width: 100%;
  height: auto;
}

.prose table {
  display: block;
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border-collapse: collapse;
  margin: 2rem 0;
  font-size: 0.95rem;
  box-shadow: var(--shadow-sm);
  border-radius: var(--radius-md);
}

.prose table th {
  background: var(--bg-elevated);
  padding: 0.85rem 1.2rem;
  text-align: left;
  font-weight: 600;
  border: 1px solid var(--border);
  color: var(--text-primary);
}

.prose table td {
  padding: 0.75rem 1.2rem;
  border: 1px solid var(--border);
  color: var(--text-secondary);
}

.prose table tr:hover td { background: var(--bg-elevated); }

/* Prev/Next navigation */
.tutorial-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.tutorial-nav-btn {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

.tutorial-nav-btn:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
  color: inherit;
}

.tutorial-nav-btn.next { flex-direction: row-reverse; text-align: right; }

.tutorial-nav-label {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  display: block;
}

.tutorial-nav-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
}

/* ============================================================
   RIGHT SIDEBAR
   ============================================================ */
.right-sidebar {
  width: 280px;
  background: var(--bg-surface);
  border-left: 1px solid var(--border);
  box-shadow: inset 4px 0 12px rgba(0, 0, 0, 0.04);
  height: calc(100vh - 70px);
  position: sticky;
  top: 70px;
  overflow-y: auto;
  padding: 1.5rem 1rem;
  flex-shrink: 0;
}

/* Light-mode right sidebar: subtle shade */
[data-theme="light"] .right-sidebar {
  background: #f8fafc;
  box-shadow: inset 4px 0 12px rgba(0, 0, 0, 0.05);
}

/* Popular tutorials widget item */
.sidebar-popular-item {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  padding: 0.5rem 0.4rem;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: var(--transition);
  color: var(--text-muted);
  font-size: 0.81rem;
  line-height: 1.4;
  border-bottom: 1px solid var(--border);
}

.sidebar-popular-item:last-child { border-bottom: none; }

.sidebar-popular-item:hover {
  color: var(--primary);
  background: var(--primary-glow);
  padding-left: 0.65rem;
}

.sidebar-popular-num {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  background: var(--bg-elevated);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.68rem;
  font-weight: 700;
  color: var(--primary);
  margin-top: 1px;
}

.sidebar-widget {
  margin-bottom: 1.75rem;
  padding-bottom: 1.75rem;
  border-bottom: 1px solid var(--border);
}

.sidebar-widget:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.sidebar-widget-title {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--primary-glow);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

/* Table of Contents */
.toc-list { display: flex; flex-direction: column; gap: 0.25rem; }

.toc-link {
  font-size: 0.82rem;
  color: var(--text-muted);
  padding: 0.3rem 0.5rem;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  transition: var(--transition);
  text-decoration: none;
  display: block;
}

.toc-link:hover, .toc-link.active {
  color: var(--primary);
  border-left-color: var(--primary);
  background: var(--primary-glow);
}

/* ============================================================
   MCQ STYLES
   ============================================================ */
.question-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  margin-bottom: 1.5rem;
  transition: var(--transition);
}

.question-number {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.75rem;
}

.question-text {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 1.25rem;
  line-height: 1.5;
}

.options-list { display: flex; flex-direction: column; gap: 0.6rem; }

.option-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: var(--transition);
  background: var(--bg-surface);
}

.option-item:hover { border-color: var(--primary); background: var(--primary-glow); }
.option-item.correct { border-color: var(--success); background: var(--success-light); }
.option-item.wrong { border-color: var(--danger); background: var(--danger-light); }
.option-item.selected { border-color: var(--primary); background: var(--primary-glow); }

.option-letter {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  border-radius: var(--radius-sm);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-muted);
}

.option-item:hover .option-letter,
.option-item.selected .option-letter { background: var(--primary); border-color: var(--primary); color: white; }
.option-item.correct .option-letter { background: var(--success); border-color: var(--success); color: white; }
.option-item.wrong .option-letter { background: var(--danger); border-color: var(--danger); color: white; }

.option-text { font-size: 0.92rem; color: var(--text-primary); padding-top: 2px; }

/* Dedicated MCQ Option Button for Practice Portal */
.mcq-option-btn {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  width: 100%;
  text-align: left;
  padding: 0.75rem 1rem;
  background: var(--bg-surface);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  font-size: 0.92rem;
  box-shadow: 0 1px 2px rgba(0,0,0,0.02);
}

.mcq-option-btn:hover {
  border-color: var(--primary);
  background: var(--bg-card-hover);
  transform: translateX(2px);
}

.mcq-opt-letter {
  width: 26px;
  height: 26px;
  border-radius: 6px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.78rem;
  color: var(--text-secondary);
  flex-shrink: 0;
  transition: var(--transition);
}

.mcq-option-btn:hover .mcq-opt-letter {
  background: var(--primary);
  border-color: var(--primary);
  color: #ffffff;
}

/* ── MCQ Chapter & Topic Sidebar Accordion ──────────────── */
.mcq-chapter-card {
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
  margin-bottom: 0.35rem;
}

.mcq-chapter-card:hover {
  border-color: rgba(108, 99, 255, 0.3);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.mcq-chapter-card.is-current-chapter {
  border-color: rgba(108, 99, 255, 0.45);
  background: var(--bg-surface);
  box-shadow: 0 3px 12px rgba(108, 99, 255, 0.08);
}

.mcq-chapter-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.65rem 0.85rem;
  gap: 0.5rem;
  background: transparent;
  transition: background 0.2s ease;
}

.mcq-chapter-header:hover {
  background: var(--bg-card-hover);
}

.mcq-chapter-link {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex: 1;
  min-width: 0;
  text-decoration: none;
  color: var(--text-primary);
}

.mcq-chapter-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 24px;
  height: 24px;
  border-radius: 6px;
  background: rgba(108, 99, 255, 0.1);
  color: var(--primary);
  font-size: 0.72rem;
  font-weight: 800;
  flex-shrink: 0;
}

.mcq-chapter-card.is-current-chapter .mcq-chapter-num {
  background: var(--primary);
  color: #ffffff;
}

.mcq-chapter-title {
  font-size: 0.86rem;
  font-weight: 600;
  line-height: 1.35;
  color: var(--text-primary);
  word-break: break-word;
  flex: 1;
}

.mcq-chapter-card.is-current-chapter .mcq-chapter-title {
  font-weight: 800;
  color: var(--primary);
}

.mcq-chapter-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 6px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.mcq-chapter-toggle:hover {
  background: rgba(108, 99, 255, 0.12);
  color: var(--primary);
}

.mcq-chapter-toggle .toggle-icon {
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.mcq-chapter-card.open .mcq-chapter-toggle .toggle-icon {
  transform: rotate(90deg);
}

.mcq-chapter-card.open .mcq-chapter-toggle {
  color: var(--primary);
}

/* Topics Drawer */
.mcq-topics-drawer {
  display: none;
  flex-direction: column;
  gap: 0.25rem;
  padding: 0.4rem 0.5rem 0.65rem 1.75rem;
  background: rgba(108, 99, 255, 0.03);
  border-top: 1px dashed var(--border);
}

.mcq-chapter-card.open .mcq-topics-drawer {
  display: flex;
}

.mcq-topic-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.42rem 0.65rem;
  border-radius: 6px;
  font-size: 0.81rem;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  transition: all 0.2s ease;
  gap: 0.5rem;
}

.mcq-topic-item:hover {
  color: var(--text-primary);
  background: var(--bg-card-hover);
}

.mcq-topic-item.active {
  color: var(--primary);
  background: rgba(108, 99, 255, 0.12);
  font-weight: 700;
}

.mcq-topic-badge {
  font-size: 0.68rem;
  font-weight: 700;
  padding: 0.15rem 0.45rem;
  border-radius: var(--radius-full);
  background: var(--bg-surface);
  color: var(--text-muted);
  border: 1px solid var(--border);
  flex-shrink: 0;
}

.mcq-topic-item.active .mcq-topic-badge {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

/* Topic Pills Horizontal Switcher Bar (Top of Questions) */
.mcq-topic-pills-bar {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  overflow-x: auto;
  padding: 0.25rem 0 0.65rem 0;
  margin-bottom: 1.25rem;
  scrollbar-width: none;
}
.mcq-topic-pills-bar::-webkit-scrollbar {
  display: none;
}

.mcq-topic-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  background: var(--bg-card);
  color: var(--text-secondary);
  border: 1px solid var(--border);
  transition: all 0.2s ease;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.03);
}

.mcq-topic-pill:hover {
  color: var(--primary);
  border-color: rgba(108, 99, 255, 0.4);
  background: var(--bg-card-hover);
}

.mcq-topic-pill.active {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
  font-weight: 700;
  box-shadow: 0 2px 8px rgba(108, 99, 255, 0.3);
}

.mcq-topic-pill-count {
  font-size: 0.7rem;
  padding: 0.1rem 0.4rem;
  border-radius: var(--radius-full);
  background: rgba(0, 0, 0, 0.08);
  font-weight: 700;
}

.mcq-topic-pill.active .mcq-topic-pill-count {
  background: rgba(255, 255, 255, 0.25);
  color: #ffffff;
}

/* Legacy fallback */
.mcq-unit-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.65rem 0.85rem;
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: all 0.2s ease;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-primary);
}

.mcq-unit-item:hover {
  background: var(--bg-card-hover);
  border-color: var(--border);
}

.mcq-unit-item.active {
  background: rgba(108, 99, 255, 0.12);
  border-color: rgba(108, 99, 255, 0.35);
  color: var(--primary);
}

.explanation-box {
  margin-top: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  padding: 0 1.25rem;
  background: rgba(16, 185, 129, 0.08);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  font-size: 0.87rem;
  color: var(--text-secondary);
  transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease, padding 0.4s cubic-bezier(0.4, 0, 0.2, 1), margin-top 0.4s cubic-bezier(0.4, 0, 0.2, 1), border-color 0.4s ease;
}

.explanation-box.show {
  margin-top: 1rem;
  max-height: 500px;
  opacity: 1;
  padding: 1rem 1.25rem;
  border-color: rgba(16, 185, 129, 0.2);
}
.explanation-box strong { color: var(--success); }

/* Question meta badges */
.question-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.25rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

.question-actions {
  margin-left: auto;
  display: flex;
  gap: 0.5rem;
}

/* ============================================================
   QUIZ INTERFACE
   ============================================================ */
.quiz-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

.quiz-header {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  margin-bottom: 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}

.quiz-timer {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.25rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--text-primary);
}

.quiz-timer.warning { color: var(--warning); }
.quiz-timer.danger { color: var(--danger); animation: pulse 1s infinite; }

.quiz-progress-bar {
  height: 4px;
  background: var(--bg-elevated);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 0.5rem;
}

.quiz-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  border-radius: var(--radius-full);
  transition: width 0.3s ease;
}

.quiz-question-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1.5rem;
}

.q-nav-dot {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: var(--transition);
}

.q-nav-dot.answered { background: var(--primary); border-color: var(--primary); color: white; }
.q-nav-dot.current { border-color: var(--primary); color: var(--primary); }

/* Quiz Result */
.quiz-result {
  text-align: center;
  padding: 3rem 1.5rem;
}

.result-score {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  margin: 0 auto 2rem;
  border: 6px solid;
  position: relative;
}

.result-score.pass {
  border-color: var(--success);
  background: var(--success-light);
  color: var(--success);
}

.result-score.fail {
  border-color: var(--danger);
  background: var(--danger-light);
  color: var(--danger);
}

.result-percentage {
  font-size: 2.5rem;
  font-weight: 900;
  line-height: 1;
}

.result-label {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* ============================================================
   FORMS
   ============================================================ */
.form-group { margin-bottom: 1.25rem; }

.form-label {
  display: block;
  font-size: 0.87rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 0.4rem;
}

.form-control {
  width: 100%;
  padding: 0.65rem 0.9rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 0.9rem;
  transition: var(--transition);
  outline: none;
}

.form-control:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.form-control::placeholder { color: var(--text-muted); }

textarea.form-control { min-height: 120px; resize: vertical; }

select.form-control {
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  padding-right: 2.5rem;
  cursor: pointer;
}

.form-text { font-size: 0.78rem; color: var(--text-muted); margin-top: 0.3rem; }
.form-error { font-size: 0.78rem; color: var(--danger); margin-top: 0.3rem; }

/* Checkbox & Radio */
.form-check {
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
  cursor: pointer;
}

.form-check-input {
  width: 18px;
  height: 18px;
  margin-top: 2px;
  flex-shrink: 0;
  accent-color: var(--primary);
  cursor: pointer;
}

.form-check-label { font-size: 0.9rem; color: var(--text-secondary); cursor: pointer; }

/* ============================================================
   ALERTS
   ============================================================ */
.alert {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.875rem 1.25rem;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  margin-bottom: 1rem;
  border: 1px solid;
}

.alert-success { background: var(--success-light); border-color: rgba(16,185,129,0.3); color: var(--success); }
.alert-danger { background: var(--danger-light); border-color: rgba(239,68,68,0.3); color: var(--danger); }
.alert-warning { background: var(--warning-light); border-color: rgba(245,158,11,0.3); color: var(--warning); }
.alert-info { background: var(--info-light); border-color: rgba(59,130,246,0.3); color: var(--info); }

/* ============================================================
   TABLES (Public)
   ============================================================ */
.table-wrap { overflow-x: auto; border-radius: var(--radius-lg); border: 1px solid var(--border); }

.table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.table th {
  background: var(--bg-elevated);
  padding: 0.875rem 1.25rem;
  text-align: left;
  font-weight: 600;
  color: var(--text-primary);
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

.table td {
  padding: 0.75rem 1.25rem;
  border-bottom: 1px solid var(--border);
  color: var(--text-secondary);
  vertical-align: middle;
}

.table tbody tr:last-child td { border-bottom: none; }
.table tbody tr:hover td { background: var(--bg-elevated); }

/* ============================================================
   TABS
   ============================================================ */
.tabs {
  display: flex;
  gap: 0.25rem;
  border-bottom: 2px solid var(--border);
  margin-bottom: 1.5rem;
  overflow-x: auto;
  scrollbar-width: none;
  /* Prevent tabs from expanding the grid parent */
  max-width: 100%;
  width: 100%;
}

.tabs::-webkit-scrollbar { display: none; }

.tab-btn {
  padding: 0.7rem 1.25rem;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-muted);
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  cursor: pointer;
  white-space: nowrap;
  transition: var(--transition);
  background: none;
}

.tab-btn:hover { color: var(--primary); }
.tab-btn.active { color: var(--primary); border-bottom-color: var(--primary); }

.tab-content { display: none; }
.tab-content.active { display: block; }

/* ============================================================
   BREADCRUMB
   ============================================================ */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.breadcrumb a { color: var(--text-muted); transition: var(--transition); }
.breadcrumb a:hover { color: var(--primary); }
.breadcrumb-sep { color: var(--text-faint); }
.breadcrumb-current { color: var(--text-primary); font-weight: 500; }

/* ============================================================
   PAGINATION
   ============================================================ */
.pagination {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  padding: 2rem 0;
}

.pagination-list {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  flex-wrap: wrap;
  justify-content: center;
}

.page-link {
  min-width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 0.5rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text-secondary);
  font-size: 0.87rem;
  font-weight: 500;
  text-decoration: none;
  transition: var(--transition);
}

.page-link:hover { border-color: var(--primary); color: var(--primary); }
.page-link.active { background: var(--primary); border-color: var(--primary); color: white; }
.page-dots { color: var(--text-muted); padding: 0 0.5rem; }
.pagination-info { font-size: 0.8rem; color: var(--text-muted); }

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  padding: 4rem 0 2rem;
  margin-top: 4rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr repeat(4, 1fr);
  gap: 2.25rem;
  margin-bottom: 3rem;
}

.footer-brand p {
  font-size: 0.87rem;
  color: var(--text-muted);
  margin-top: 0.75rem;
  line-height: 1.6;
}

.footer-heading {
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

.footer-links { display: flex; flex-direction: column; gap: 0.6rem; }

.footer-link {
  font-size: 0.87rem;
  color: var(--text-muted);
  transition: var(--transition);
  text-decoration: none;
}

.footer-link:hover { color: var(--primary); }

.footer-social-icon {
  width: 34px;
  height: 34px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.78rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: all 0.25s ease;
}

.footer-social-icon:hover {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
  transform: translateY(-2px);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--text-muted);
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* ============================================================
   AD UNITS
   ============================================================ */
.ad-unit {
  margin: 1.5rem 0;
  border-radius: var(--radius-md);
  overflow: hidden;
}

.ad-image { width: 100%; border-radius: var(--radius-md); }

.ad-placeholder {
  background: var(--bg-elevated);
  border: 2px dashed var(--border);
  border-radius: var(--radius-md);
  padding: 2rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* ============================================================
   ANIMATIONS
   ============================================================ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.animate-in { animation: fadeInUp 0.5s ease both; }
.animate-fade { animation: fadeIn 0.4s ease both; }

/* Skeleton loader */
.skeleton {
  background: linear-gradient(90deg, var(--bg-elevated) 25%, var(--bg-card-hover) 50%, var(--bg-elevated) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--radius-md);
}

/* ============================================================
   EMPTY STATE
   ============================================================ */
.empty-state {
  text-align: center;
  padding: 4rem 1.5rem;
  color: var(--text-muted);
}

.empty-state svg { margin-bottom: 1rem; opacity: 0.5; }
.empty-state h3 { font-size: 1.1rem; margin-bottom: 0.5rem; color: var(--text-secondary); }
.empty-state p { font-size: 0.87rem; margin-bottom: 1.5rem; }

/* ============================================================
   UTILITY CLASSES
   ============================================================ */
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }
.p-0 { padding: 0 !important; }
.d-none { display: none; }
.d-flex { display: flex; }
.d-block { display: block; }
.d-grid { display: grid; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.overflow-hidden { overflow: hidden; }
.opacity-0 { opacity: 0; }
.opacity-50 { opacity: 0.5; }
.rounded { border-radius: var(--radius-md); }
.rounded-full { border-radius: var(--radius-full); }
.border { border: 1px solid var(--border); }
.shadow { box-shadow: var(--shadow-md); }
.fw-bold { font-weight: 700; }
.fw-semibold { font-weight: 600; }

/* Grid helpers — min-width:0 prevents overflow in grid cells */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.5rem; min-width: 0; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; min-width: 0; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; min-width: 0; }
.grid-auto { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(250px, 100%), 1fr)); gap: 1.5rem; }
.grid-2 > *, .grid-3 > *, .grid-4 > *, .grid-auto > * { min-width: 0; max-width: 100%; }

/* ============================================================
   FILTER DRAWER (Mobile Sidebar Filters)
   ============================================================ */
.filter-toggle-btn {
  display: none;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.1rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: var(--transition);
  min-height: 44px;
}

.filter-toggle-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.filter-toggle-btn .filter-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 20px;
  height: 20px;
  background: var(--primary);
  color: white;
  border-radius: 50%;
  font-size: 0.72rem;
  font-weight: 700;
}

.filter-drawer-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  backdrop-filter: blur(4px);
  z-index: 250;
}

.filter-drawer-overlay.open { display: block; }

.filter-drawer {
  position: fixed;
  top: 0;
  left: -320px;
  width: 300px;
  height: 100%;
  background: var(--bg-surface);
  border-right: 1px solid var(--border);
  z-index: 260;
  overflow-y: auto;
  padding: 1.5rem;
  transition: left 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.filter-drawer.open { left: 0; }

.filter-drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.5rem;
}

.filter-drawer-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
}

.filter-drawer-close {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition);
}

.filter-drawer-close:hover { color: var(--danger); border-color: var(--danger); }

/* Page-level sidebar layout used on MCQ/Jobs/Search/Blog */
.page-with-sidebar {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 2rem;
  align-items: start;
  min-width: 0;
}
.page-with-sidebar > * {
  min-width: 0;
  max-width: 100%;
}

.page-sidebar {
  /* Desktop: sticky sidebar */
  position: sticky;
  top: 90px;
  align-self: start;
  max-height: calc(100vh - 110px);
  overflow-y: auto;
  scrollbar-width: thin;
}

.page-sidebar::-webkit-scrollbar { width: 3px; }
.page-sidebar::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 2px; }

.page-sidebar-mobile-bar {
  display: none;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

/* Homepage utility classes */
.search-form-bar {
  display: flex;
  gap: 0.75rem;
  background: var(--bg-elevated);
  padding: 0.5rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
}

.newsletter-form {
  display: flex;
  gap: 0.5rem;
  background: var(--bg-elevated);
  padding: 0.4rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
}

/* Table responsiveness */
.table-responsive {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  width: 100%;
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1400px) {
  .tutorial-content {
    padding: 3rem 2rem;
  }
}

@media (max-width: 1300px) {
  .navbar-inner { gap: 1rem; }
  .navbar-nav { gap: 0.1rem; }
  .nav-link { padding: 0.4rem 0.6rem; font-size: 0.83rem; }
  .search-trigger { min-width: 140px; }
}

@media (max-width: 1200px) {
  .layout-three-col {
    grid-template-columns: 240px 1fr;
    background: linear-gradient(
      to right,
      var(--sidebar-bg) 240px,
      transparent 240px
    );
  }
  .tutorial-sidebar {
    width: 240px;

  }
  .right-sidebar { display: none; }
  .navbar-brand-name { display: none; }
  .navbar-username { display: none; }
  .search-trigger {
    min-width: auto;
    width: 38px;
    height: 38px;
    padding: 0;
    justify-content: center;
    border-radius: var(--radius-md);
  }
  .search-trigger kbd { display: none; }
  .search-trigger .search-hint-text { display: none; }
  .tutorial-content {
    padding: 2.5rem 2rem;
  }
}

@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(3, 1fr); }
  .page-with-sidebar { grid-template-columns: 220px 1fr; gap: 1.5rem; }
}

/* ─── Tablet Landscape ─── */
@media (max-width: 992px) {
  .navbar-inner { gap: 0.5rem; padding: 0 1rem; }
  .navbar-actions { gap: 0.35rem; }
  .navbar-nav { display: none; }
  .hamburger { display: flex; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 2rem; }
  /* Grid: 2-col tablet step */
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  /* Page sidebar layout: show filter toggle */
  .page-with-sidebar {
    grid-template-columns: 1fr;
  }
  .page-sidebar {
    display: none;
  }
  .filter-toggle-btn { display: inline-flex; }
  .page-sidebar-mobile-bar { display: flex; }
  /* Section header stacking */
  .section-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
  }
}

/* ─── Tablet Portrait ─── */
@media (max-width: 768px) {
  /* Navbar mobile */
  .navbar { height: 60px; }
  .navbar.scrolled { height: 56px; }
  .navbar-inner { padding: 0 0.875rem; gap: 0.4rem; }
  .navbar-actions { gap: 0.3rem; }
  .navbar-logo { width: 34px; height: 34px; font-size: 0.88rem; }
  .navbar-brand-name { display: none; }
  /* Search: icon only, no border pill */
  .search-trigger {
    width: 36px;
    height: 36px;
    min-width: 36px;
    padding: 0;
    border-radius: var(--radius-md);
    justify-content: center;
  }
  .search-trigger kbd,
  .search-trigger .search-hint-text { display: none; }
  /* Theme toggle: keep but compact */
  .theme-toggle { width: 36px; height: 36px; }
  /* Hamburger compact */
  .hamburger { width: 36px; height: 36px; }
  /* Login button compact */
  .btn.btn-primary.btn-sm { padding: 0.4rem 0.75rem; font-size: 0.82rem; min-height: 36px; }
  .layout-three-col { 
    grid-template-columns: 1fr;
    background: none; /* sidebar is a floating drawer on mobile */
  }
  .tutorial-sidebar {
    position: fixed;
    left: -100%;
    z-index: 160; /* Higher than #sidebar-overlay (z-index: 150) */
    transition: left 0.3s ease;
    width: 285px;
    height: 100vh;
    top: 0;
  }
  .tutorial-sidebar.open { left: 0; }
  .tutorial-content { padding: 1.5rem 1rem; }
  /* Prose improvements */
  .prose { font-size: 1rem; }
  .prose h1 { font-size: 1.7rem; }
  .prose h2 { font-size: 1.35rem; }
  .prose h3 { font-size: 1.15rem; }
  .prose pre { padding: 1rem; font-size: 0.82rem; }
  .prose img, .prose video, .prose iframe { margin: 1.25rem 0; }
  /* Grid collapse */
  .hero-paths { grid-template-columns: 1fr; }
  .grid-2 { grid-template-columns: 1fr; }
  .grid-3 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 1.5rem; }
  .footer { padding: 2.5rem 0 1.5rem; margin-top: 2rem; }
  .hero-stats { gap: 1rem; flex-wrap: wrap; }
  .stat-divider { display: none; }
  .tutorial-nav { grid-template-columns: 1fr; }
  .section { padding: 2.5rem 0; }
  .section-sm { padding: 1.75rem 0; }
  /* Touch targets */
  .btn { min-height: 44px; }
  .btn-sm { min-height: 40px; }
  .page-link { min-width: 40px; height: 40px; }
  .tab-btn { min-height: 44px; padding: 0.75rem 1rem; }
  .option-item { min-height: 48px; padding: 0.85rem 1rem; }
  /* Form inputs */
  .form-control { padding: 0.75rem 1rem; font-size: 1rem; min-height: 48px; }
  /* Search box */
  .search-box { margin: 0 0.875rem; }
  /* Quiz */
  .quiz-container { padding: 1.25rem 1rem; }
  .quiz-header { flex-direction: column; align-items: flex-start; }
  /* Tutorial nav */
  .tutorial-nav-btn { padding: 0.75rem 1rem; }
  /* MCQ question meta */
  .question-meta { flex-wrap: wrap; gap: 0.5rem; }
  .question-actions { margin-left: 0; width: 100%; justify-content: flex-end; }
  /* Hero */
  .hero { padding: 3rem 0 3.5rem; }
  .hero-title { margin-bottom: 1rem; }
  .hero-subtitle { font-size: 1rem; margin-bottom: 1.5rem; }
  /* Blog featured post */
  .blog-featured-card { grid-template-columns: 1fr !important; }
  .blog-featured-card > div:first-child { min-height: 200px !important; }
  /* Page-level content padding */
  .container { padding-left: 0.875rem; padding-right: 0.875rem; }
}

/* ─── Large Phones ─── */
@media (max-width: 600px) {
  .grid-4 { grid-template-columns: 1fr; }
  /* Search form stacking */
  .search-form-bar {
    flex-direction: column;
    gap: 0.5rem;
  }
  .search-form-bar input {
    width: 100%;
  }
  .search-form-bar .btn {
    width: 100%;
    justify-content: center;
  }
  /* Newsletter form stacking */
  .newsletter-form {
    flex-direction: column;
    padding: 0.75rem;
    gap: 0.5rem;
  }
  .newsletter-form input {
    width: 100%;
    padding: 0.65rem 0.75rem;
  }
  .newsletter-form .btn {
    width: 100%;
    justify-content: center;
    border-radius: var(--radius-md) !important;
  }
  /* Stats cards */
  .hero-stats { flex-direction: column; align-items: flex-start; gap: 1.25rem; }
  /* Footer bottom */
  .footer-bottom { flex-direction: column; text-align: center; gap: 0.5rem; }
  /* Section header */
  .section-header { flex-direction: column; align-items: flex-start; }
  .section-header .btn { align-self: flex-start; }
}

/* ─── Standard Phones ─── */
@media (max-width: 480px) {
  .container { padding: 0 0.875rem; }
  h1 { font-size: 1.6rem; }
  h2 { font-size: 1.3rem; }
  /* Keep theme toggle compact on small phones */
  .theme-toggle { width: 34px; height: 34px; display: inline-flex; align-items: center; justify-content: center; }
  /* Ensure search icon stays small */
  .search-trigger { width: 34px; height: 34px; min-width: 34px; }
  /* Hamburger */
  .hamburger { width: 34px; height: 34px; }
  .navbar-logo { width: 32px; height: 32px; font-size: 0.82rem; }
  .navbar-inner { padding: 0 0.75rem; gap: 0.3rem; }
  .navbar-actions { gap: 0.25rem; }
  .grid-auto { grid-template-columns: 1fr; }
  /* Card padding reduction */
  .card { padding: 1.1rem; }
  .question-card { padding: 1.25rem 1rem; }
  .path-card { padding: 1.25rem 1rem; }
  .blog-card-body { padding: 1rem; }
  /* Section */
  .section { padding: 2rem 0; }
  /* Pagination */
  .pagination-list { gap: 0.2rem; }
  .page-link { min-width: 36px; height: 36px; font-size: 0.82rem; }
  /* Footer */
  .footer { padding: 2rem 0 1.25rem; }
  .footer-grid { gap: 1.25rem; }
  .footer-heading { margin-bottom: 0.5rem; }
  /* Breadcrumb */
  .breadcrumb { font-size: 0.78rem; }
  /* Mobile nav drawer width */
  .mobile-nav-drawer { width: 85vw; max-width: 300px; }
  /* Tutorial meta */
  .tutorial-meta { gap: 0.75rem; flex-wrap: wrap; }
  .tutorial-share { margin-left: 0; width: 100%; }
  /* Tabs */
  .tabs { gap: 0; }
  .tab-btn { padding: 0.6rem 0.75rem; font-size: 0.82rem; min-height: 40px; }
  /* Alert */
  .alert { padding: 0.75rem 1rem; font-size: 0.85rem; }
  /* Login btn on mobile */
  .btn.btn-primary.btn-sm { padding: 0.35rem 0.65rem; font-size: 0.8rem; min-height: 34px; }
}

/* ─── iPhone SE / Smallest Phones ─── */
@media (max-width: 375px) {
  .container { padding: 0 0.625rem; }
  .navbar-inner { padding: 0 0.625rem; gap: 0.2rem; }
  .navbar-logo { width: 30px; height: 30px; font-size: 0.78rem; }
  .navbar-actions { gap: 0.2rem; }
  .hamburger { width: 32px; height: 32px; }
  .search-trigger { width: 32px; height: 32px; min-width: 32px; }
  .hero { padding: 2.5rem 0 3rem; }
  .hero-title { font-size: 1.5rem; }
  .path-card { padding: 1rem 0.875rem; }
  .path-title { font-size: 1.05rem; }
  .mobile-nav-drawer { width: 90vw; }
  .btn-lg { padding: 0.75rem 1.5rem; font-size: 0.95rem; }
  /* Prevent any horizontal overflow */
  html, body { overflow-x: hidden; }
  img, video, iframe, pre, table { max-width: 100%; }
}

/* ============================================================
   PROFILE GRID
   ============================================================ */
.profile-grid {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 2rem;
  align-items: start;
  min-width: 0;
}
.profile-grid > * { min-width: 0; max-width: 100%; }
@media (max-width: 768px) {
  .profile-grid { grid-template-columns: 1fr; }
}

/* ============================================================
   CONTENT WITH RIGHT SIDEBAR (blog post, job details)
   Main content left + narrow sidebar right, collapses on mobile
   ============================================================ */
.content-with-sidebar {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 2.5rem;
  align-items: start;
  /* Critical: prevent grid children from overflowing */
  min-width: 0;
}
.content-with-sidebar > * {
  min-width: 0;
  max-width: 100%;
}
@media (max-width: 992px) {
  .content-with-sidebar {
    grid-template-columns: 1fr;
  }
  .content-with-sidebar > aside {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
  }
}
@media (max-width: 768px) {
  .content-with-sidebar {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

/* ============================================================
   UX SKELETON LOADERS & MICRO-TRANSITIONS
   ============================================================ */
.skeleton {
  background: linear-gradient(90deg, var(--bg-elevated) 25%, var(--border) 50%, var(--bg-elevated) 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite linear;
  border-radius: var(--radius-sm);
  display: inline-block;
  width: 100%;
  height: 1.25rem;
}
@keyframes skeleton-shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}
.skeleton-text { height: 1rem; margin-bottom: 0.5rem; }
.skeleton-title { height: 1.75rem; margin-bottom: 1rem; width: 70%; }
.skeleton-card { height: 200px; border-radius: var(--radius-lg); }

.search-spinner {
  width: 20px;
  height: 20px;
  border: 2px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s infinite linear;
  display: inline-block;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Error page layouts */
.error-page-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: calc(100vh - 140px);
  text-align: center;
  padding: 2rem;
}
.error-code {
  font-size: clamp(4rem, 15vw, 8rem);
  font-weight: 900;
  line-height: 1;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 1rem;
}
.error-title {
  font-size: 1.75rem;
  font-weight: 800;
  margin-bottom: 1rem;
}
.error-message {
  color: var(--text-muted);
  max-width: 500px;
  margin-bottom: 2rem;
  font-size: 0.95rem;
}

/* Sidebar Overlay */
#sidebar-overlay.show {
  display: block !important;
}

/* Micro-animations */
.btn, .nav-link, .sidebar-topic, .theme-toggle, .hamburger {
  transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}
.btn:active, .theme-toggle:active, .hamburger:active {
  transform: scale(0.96);
}

/* ============================================================
   TUTORIAL CARD — Learning-oriented (blue/teal palette)
   ============================================================ */
.tutorial-card {
  display: flex;
  flex-direction: column;
  background: var(--bg-card);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-top: 3px solid #3b82f6;
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  text-decoration: none;
  color: inherit;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s ease, border-color 0.3s ease;
  position: relative;
  overflow: hidden;
  height: 100%;
}

.tutorial-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: linear-gradient(135deg, rgba(59,130,246,0.04) 0%, transparent 60%);
  pointer-events: none;
}

.tutorial-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 32px rgba(59, 130, 246, 0.15);
  border-color: rgba(59, 130, 246, 0.5);
  color: inherit;
}

.tutorial-card-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.65rem;
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.25);
  border-radius: var(--radius-full);
  font-size: 0.68rem;
  font-weight: 700;
  color: #60a5fa;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  margin-bottom: 0.85rem;
}

.tutorial-card-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: rgba(59, 130, 246, 0.12);
  color: #60a5fa;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 0.85rem;
  transition: transform 0.2s ease;
}

.tutorial-card:hover .tutorial-card-icon {
  transform: scale(1.1) rotate(-3deg);
}

.tutorial-card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

.tutorial-card-desc {
  font-size: 0.84rem;
  color: var(--text-muted);
  line-height: 1.55;
  flex: 1;
  margin-bottom: 1.1rem;
}

.tutorial-card-footer {
  margin-top: auto;
  padding-top: 0.85rem;
  border-top: 1px solid rgba(59, 130, 246, 0.12);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.btn-start-learning {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 1rem;
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.3);
  border-radius: var(--radius-md);
  font-size: 0.83rem;
  font-weight: 700;
  color: #60a5fa;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn-start-learning:hover,
.tutorial-card:hover .btn-start-learning {
  background: #3b82f6;
  border-color: #3b82f6;
  color: white;
  box-shadow: 0 0 16px rgba(59, 130, 246, 0.35);
}

/* ============================================================
   TEST CARD — Assessment-oriented (orange/amber palette)
   ============================================================ */
.test-card {
  display: flex;
  flex-direction: column;
  background: var(--bg-card);
  border: 1px solid rgba(245, 158, 11, 0.2);
  border-top: 3px solid #f59e0b;
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s ease, border-color 0.3s ease;
  position: relative;
  overflow: hidden;
  gap: 0.75rem;
}

.test-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: linear-gradient(135deg, rgba(245,158,11,0.04) 0%, transparent 60%);
  pointer-events: none;
}

.test-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 32px rgba(245, 158, 11, 0.15);
  border-color: rgba(245, 158, 11, 0.5);
}

.test-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 0.75rem;
}

.test-card-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.22rem 0.6rem;
  background: rgba(245, 158, 11, 0.12);
  border: 1px solid rgba(245, 158, 11, 0.3);
  border-radius: var(--radius-full);
  font-size: 0.65rem;
  font-weight: 700;
  color: #fbbf24;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  flex-shrink: 0;
}

.test-card-title {
  font-size: 0.97rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
  flex: 1;
  line-height: 1.35;
}

.test-card-meta {
  display: flex;
  gap: 0.65rem;
  flex-wrap: wrap;
  font-size: 0.77rem;
  color: var(--text-muted);
}

.test-card-meta-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.22rem 0.6rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 600;
}

.test-card-meta-chip.chip-time { color: #fbbf24; border-color: rgba(245,158,11,0.25); background: rgba(245,158,11,0.07); }
.test-card-meta-chip.chip-questions { color: #a78bfa; border-color: rgba(167,139,250,0.25); background: rgba(167,139,250,0.07); }
.test-card-meta-chip.chip-pass { color: #34d399; border-color: rgba(52,211,153,0.25); background: rgba(52,211,153,0.07); }

.test-card-desc {
  font-size: 0.83rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin: 0;
  flex: 1;
}

.test-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: auto;
  padding-top: 0.85rem;
  border-top: 1px solid rgba(245, 158, 11, 0.12);
}

.btn-take-test {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.55rem 1.15rem;
  background: linear-gradient(135deg, #f59e0b, #d97706);
  border: none;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  font-weight: 700;
  color: white;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  white-space: nowrap;
  box-shadow: 0 2px 8px rgba(245, 158, 11, 0.25);
}

.btn-take-test:hover {
  background: linear-gradient(135deg, #d97706, #b45309);
  color: white;
  box-shadow: 0 4px 20px rgba(245, 158, 11, 0.4);
  transform: translateY(-1px);
}

/* ============================================================
   TEST CALLOUT — In tutorial pages
   ============================================================ */
.test-callout {
  margin-top: 2.5rem;
  background: linear-gradient(135deg, rgba(245,158,11,0.08) 0%, rgba(251,191,36,0.04) 100%);
  border: 1px solid rgba(245, 158, 11, 0.25);
  border-left: 4px solid #f59e0b;
  border-radius: var(--radius-lg);
  padding: 1.5rem 1.75rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.25rem;
}

.test-callout-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: rgba(245, 158, 11, 0.15);
  color: #f59e0b;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.test-callout-body h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0 0 0.3rem 0;
}

.test-callout-body p {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin: 0;
}

/* ============================================================
   SHOW ANSWER / REVEAL ANSWER BUTTON
   ============================================================ */
.btn-reveal-answer {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.25rem;
  background: linear-gradient(135deg, rgba(16,185,129,0.12), rgba(16,185,129,0.06));
  border: 1.5px solid rgba(16, 185, 129, 0.4);
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--success);
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
  min-height: 42px;
  letter-spacing: 0.01em;
}

.btn-reveal-answer:hover {
  background: var(--success);
  border-color: var(--success);
  color: white;
  box-shadow: 0 4px 16px rgba(16, 185, 129, 0.35);
  transform: translateY(-1px);
}

.btn-reveal-answer:active {
  transform: scale(0.97);
}

.btn-reveal-answer:disabled,
.btn-reveal-answer.answered {
  background: var(--success-light);
  border-color: rgba(16,185,129,0.3);
  color: var(--success);
  cursor: default;
  transform: none;
  box-shadow: none;
  opacity: 0.8;
}

/* ============================================================
   SIDEBAR LAYOUT FIX — Full-height, no empty space
   ============================================================ */
.page-with-sidebar {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 0;
  align-items: stretch;
  min-width: 0;
}

.page-with-sidebar > * {
  min-width: 0;
  max-width: 100%;
}

/* Sidebar fills full column height */
.page-sidebar-full {
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  padding: 1.5rem 1rem;
  min-height: 100%;
  align-self: stretch;
}

[data-theme="light"] .page-sidebar-full {
  background: #f8fafc;
}

/* Inner sticky content within sidebar */
.page-sidebar-sticky {
  position: sticky;
  top: 90px;
  max-height: calc(100vh - 110px);
  overflow-y: auto;
  scrollbar-width: thin;
}

.page-sidebar-sticky::-webkit-scrollbar { width: 3px; }
.page-sidebar-sticky::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 2px; }

/* Main content area beside sidebar */
.page-main-content {
  padding: 2rem 2rem 4rem 2rem;
  min-width: 0;
}

@media (max-width: 992px) {
  .page-with-sidebar {
    grid-template-columns: 1fr;
    gap: 0;
  }
  .page-sidebar-full {
    display: none;
  }
  .page-main-content {
    padding: 1.5rem 1rem 3rem 1rem;
  }
}

/* ============================================================
   MCQ SIDEBAR — responsive hide on tablet/mobile
   ============================================================ */
@media (max-width: 992px) {
  .mcq-sidebar-desktop {
    display: none !important;
  }
  div[style*="grid-template-columns:240px 1fr"] {
    grid-template-columns: 1fr !important;
  }
}

/* ============================================================
   TOPIC CARD ITEM — Learning (blue) vs Test (orange) split
   ============================================================ */
.topic-row {
  display: flex;
  align-items: stretch;
  background: var(--bg-card);
  border: 1px solid rgba(255,255,255,0.07);
  border-radius: 10px;
  overflow: hidden;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
  position: relative;
}

.topic-row:hover {
  border-color: rgba(59,130,246,0.35);
  box-shadow: 0 4px 16px rgba(0,0,0,0.3);
}

.topic-row-learn {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: 1;
  min-width: 0;
  padding: 0.9rem 1rem;
  text-decoration: none;
  color: var(--text-secondary);
  border-right: 1px solid rgba(255,255,255,0.05);
  transition: background 0.15s ease, color 0.15s ease;
}

.topic-row-learn:hover {
  background: rgba(59,130,246,0.06);
  color: #60a5fa;
}

.topic-row-learn:hover .topic-num {
  background: rgba(59,130,246,0.2);
  color: #60a5fa;
}

.topic-num {
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: rgba(255,255,255,0.06);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.72rem;
  font-weight: 700;
  flex-shrink: 0;
  transition: background 0.15s ease, color 0.15s ease;
}

.topic-title {
  flex: 1;
  font-size: 0.875rem;
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.topic-time {
  font-size: 0.72rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.2rem;
  flex-shrink: 0;
}

.topic-row-test {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  padding: 0 1rem;
  min-width: 90px;
  font-size: 0.76rem;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(135deg, #f59e0b, #d97706);
  text-decoration: none;
  transition: background 0.2s ease;
  flex-shrink: 0;
  white-space: nowrap;
}

.topic-row-test:hover {
  background: linear-gradient(135deg, #d97706, #b45309);
  color: #fff;
}

/* ============================================================
   TOPIC ROW — Mobile responsive
   ============================================================ */
@media (max-width: 600px) {
  .topic-row-learn {
    padding: 0.75rem 0.75rem;
    gap: 0.55rem;
  }
  .topic-title {
    font-size: 0.83rem;
  }
  .topic-time {
    display: none; /* hide read-time on very small screens to save space */
  }
  .topic-row-test {
    min-width: 72px;
    padding: 0 0.65rem;
    font-size: 0.7rem;
    gap: 0.2rem;
  }
  /* Chapter header on mobile */
  .topic-chapter-header {
    flex-wrap: wrap;
    gap: 0.5rem;
  }
}

/* ============================================================
   STUDYNEXACADEMY — MODERN VISUAL DESIGN SYSTEM 2.5
   Rich Aesthetics, Dynamic Mesh Gradients, Micro-Animations,
   Layered Card Depth, and Interactive Hover Effects
   ============================================================ */

/* 1. Global Color Gradients & Ambient Lighting Tokens */
:root {
  --grad-primary: linear-gradient(135deg, #6366f1 0%, #4f46e5 100%);
  --grad-indigo: linear-gradient(135deg, #6366f1 0%, #818cf8 100%);
  --grad-emerald: linear-gradient(135deg, #10b981 0%, #059669 100%);
  --grad-amber: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
  --grad-cyan: linear-gradient(135deg, #06b6d4 0%, #0284c7 100%);
  --grad-rose: linear-gradient(135deg, #f43f5e 0%, #e11d48 100%);
  --grad-purple: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
  --grad-sunset: linear-gradient(135deg, #ec4899 0%, #f43f5e 50%, #f59e0b 100%);

  --shadow-card-hover: 0 16px 36px -8px rgba(99, 102, 241, 0.18), 0 4px 12px -2px rgba(15, 23, 42, 0.06);
  --shadow-card-glow: 0 0 20px -3px rgba(99, 102, 241, 0.25);
  --ease-spring: cubic-bezier(0.16, 1, 0.3, 1);
}

[data-theme="dark"] {
  --shadow-card-hover: 0 16px 40px -8px rgba(0, 0, 0, 0.6), 0 0 25px -4px rgba(99, 102, 241, 0.3);
  --shadow-card-glow: 0 0 25px -2px rgba(99, 102, 241, 0.35);
}

/* 2. Keyframes & Micro-Animations */
@keyframes fadeInUp {
  0% {
    opacity: 0;
    transform: translateY(16px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes floatSlow {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-5px); }
}

@keyframes pulseGlow {
  0%, 100% { opacity: 0.6; transform: scale(1); }
  50% { opacity: 1; transform: scale(1.08); }
}

@keyframes shimmerSweep {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

@keyframes popIn {
  0% { transform: scale(0.92); opacity: 0; }
  70% { transform: scale(1.03); }
  100% { transform: scale(1); opacity: 1; }
}

/* 3. Section Ambient Canvas & Alternating Mesh */
.section {
  position: relative;
  padding: 3.5rem 0;
}

.section-alt {
  background: linear-gradient(180deg, rgba(99, 102, 241, 0.03) 0%, rgba(139, 92, 246, 0.02) 50%, transparent 100%);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

/* 4. Section Badge Pills System (.sec-badge) */
.sec-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.32rem 0.85rem;
  border-radius: 9999px;
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 0.65rem;
  border: 1px solid transparent;
  transition: all 0.25s var(--ease-spring);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
}

.sec-badge:hover {
  transform: translateY(-1.5px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.sec-badge-indigo {
  background: rgba(99, 102, 241, 0.12);
  color: #6366f1;
  border-color: rgba(99, 102, 241, 0.28);
}
[data-theme="dark"] .sec-badge-indigo {
  background: rgba(99, 102, 241, 0.2);
  color: #a5b4fc;
}

.sec-badge-emerald {
  background: rgba(16, 185, 129, 0.12);
  color: #059669;
  border-color: rgba(16, 185, 129, 0.28);
}
[data-theme="dark"] .sec-badge-emerald {
  background: rgba(16, 185, 129, 0.2);
  color: #6ee7b7;
}

.sec-badge-amber {
  background: rgba(245, 158, 11, 0.12);
  color: #d97706;
  border-color: rgba(245, 158, 11, 0.28);
}
[data-theme="dark"] .sec-badge-amber {
  background: rgba(245, 158, 11, 0.2);
  color: #fcd34d;
}

.sec-badge-cyan {
  background: rgba(6, 182, 212, 0.12);
  color: #0891b2;
  border-color: rgba(6, 182, 212, 0.28);
}
[data-theme="dark"] .sec-badge-cyan {
  background: rgba(6, 182, 212, 0.2);
  color: #67e8f9;
}

.sec-badge-purple {
  background: rgba(168, 85, 247, 0.12);
  color: #9333ea;
  border-color: rgba(168, 85, 247, 0.28);
}
[data-theme="dark"] .sec-badge-purple {
  background: rgba(168, 85, 247, 0.2);
  color: #d8b4fe;
}

.sec-badge-rose {
  background: rgba(244, 63, 94, 0.12);
  color: #e11d48;
  border-color: rgba(244, 63, 94, 0.28);
}
[data-theme="dark"] .sec-badge-rose {
  background: rgba(244, 63, 94, 0.2);
  color: #fda4af;
}

/* 5. Modern Section Headings & Action Buttons */
.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 1.25rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.section-title {
  font-size: clamp(1.4rem, 3.2vw, 1.95rem);
  font-weight: 900;
  color: var(--text-primary);
  letter-spacing: -0.025em;
  line-height: 1.25;
  margin-bottom: 0.35rem;
}

.section-title span {
  background: var(--grad-indigo);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-subtitle {
  font-size: 0.92rem;
  color: var(--text-muted);
  max-width: 620px;
  line-height: 1.5;
  margin: 0;
}

.section-action-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  padding: 0.45rem 1rem;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  transition: all 0.22s var(--ease-spring);
  box-shadow: var(--shadow-sm);
}

.section-action-btn:hover {
  color: #ffffff;
  background: var(--grad-primary);
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px -3px rgba(99, 102, 241, 0.35);
}

/* 6. High-Tier Card System & Micro-Interactions */
/* 6. Clean, High-Tier Card System (Stable & Elegant) */
.card,
.subject-card,
.test-card,
.mcq-cat-card,
.past-paper-q-card,
.question-card,
.blog-card,
.feature-card {
  background: var(--bg-card);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-lg);
  position: relative;
  overflow: hidden;
  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.04);
}

/* ONLY Clickable Link Cards get a clean, subtle 2px hover effect */
a.card:hover,
a.subject-card:hover,
a.test-card:hover,
a.mcq-cat-card:hover,
a.past-paper-q-card:hover,
a.blog-card:hover,
a.feature-card:hover {
  transform: translateY(-2.5px);
  border-color: rgba(99, 102, 241, 0.38);
  box-shadow: 0 10px 24px -4px rgba(15, 23, 42, 0.08), 0 2px 6px -1px rgba(99, 102, 241, 0.1);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

/* Clickable card chevron slide */
a.card:hover span[style*="chevron"],
a.card:hover svg[data-icon="chevron-right"],
a.card:hover svg:last-child,
a.subject-card:hover svg {
  transform: translateX(3px);
  transition: transform 0.18s ease;
}

/* Card top subtle color accent line */
a.card::before,
a.subject-card::before,
a.test-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2.5px;
  background: linear-gradient(90deg, #6366f1, #8b5cf6, #3b82f6);
  opacity: 0;
  transition: opacity 0.2s ease;
}

a.card:hover::before,
a.subject-card:hover::before,
a.test-card:hover::before {
  opacity: 1;
}

/* 7. Enhanced Hero Banner Gradients & Highlights */
.hero-section {
  position: relative;
  padding: 4rem 0 3.25rem;
  background: radial-gradient(circle at 50% 15%, rgba(99, 102, 241, 0.12) 0%, rgba(139, 92, 246, 0.05) 45%, transparent 70%), var(--bg-base);
  border-bottom: 1px solid var(--border);
  overflow: hidden;
}

.hero-section::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 5%;
  right: 5%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.35), transparent);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid rgba(99, 102, 241, 0.25);
  color: var(--primary);
  padding: 0.4rem 1.2rem;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 800;
  margin-bottom: 1.25rem;
  backdrop-filter: blur(8px);
  box-shadow: 0 2px 10px rgba(99, 102, 241, 0.12);
  transition: all 0.25s ease;
}

.hero-badge:hover {
  transform: translateY(-2px);
  background: rgba(99, 102, 241, 0.16);
  border-color: rgba(99, 102, 241, 0.4);
}

.quote-box {
  background: var(--bg-surface);
  border: 1.5px solid var(--border);
  border-left: 4px solid var(--primary) !important;
  padding: 0.85rem 1.4rem;
  border-radius: var(--radius-md);
  max-width: 640px;
  margin: 0 auto 2rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
  min-height: 54px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.25s ease;
}

.quote-box:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(15, 23, 42, 0.06);
  border-color: rgba(99, 102, 241, 0.3);
}

/* 8. Interactive MCQ Option Buttons (.mcq-option-btn) */
.mcq-option-btn {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  width: 100%;
  text-align: left;
  padding: 0.85rem 1.15rem;
  background: var(--bg-surface);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 0.92rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.22s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
}

.mcq-option-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--primary);
  transform: translateX(4px);
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.12);
}

.mcq-option-btn:active {
  transform: scale(0.985);
}

.mcq-opt-letter {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  border: 1.5px solid var(--border);
  background: var(--bg-elevated);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.8rem;
  color: var(--text-muted);
  flex-shrink: 0;
  transition: all 0.2s ease;
}

.mcq-option-btn:hover .mcq-opt-letter {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--primary-glow);
}

.mcq-option-btn.selected-correct {
  background: rgba(16, 185, 129, 0.14) !important;
  border-color: #10b981 !important;
  color: #065f46 !important;
  animation: popIn 0.3s var(--ease-spring);
}
[data-theme="dark"] .mcq-option-btn.selected-correct {
  color: #6ee7b7 !important;
}
.mcq-option-btn.selected-correct .mcq-opt-letter {
  background: #10b981 !important;
  color: #ffffff !important;
  border-color: #10b981 !important;
}

.mcq-option-btn.selected-wrong {
  background: rgba(239, 68, 68, 0.14) !important;
  border-color: #ef4444 !important;
  color: #991b1b !important;
  animation: popIn 0.3s var(--ease-spring);
}
[data-theme="dark"] .mcq-option-btn.selected-wrong {
  color: #fca5a5 !important;
}
.mcq-option-btn.selected-wrong .mcq-opt-letter {
  background: #ef4444 !important;
  color: #ffffff !important;
  border-color: #ef4444 !important;
}

/* 9. Modern Buttons with Radiant Gradients */
.btn-primary {
  background: linear-gradient(135deg, #6366f1 0%, #4f46e5 50%, #4338ca 100%);
  color: #ffffff !important;
  border: none;
  font-weight: 700;
  box-shadow: 0 4px 14px rgba(79, 70, 229, 0.32);
  transition: all 0.24s cubic-bezier(0.34, 1.56, 0.64, 1);
  border-radius: var(--radius-md);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #4f46e5 0%, #4338ca 50%, #3730a3 100%);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(79, 70, 229, 0.48);
}

.btn-primary:active {
  transform: scale(0.97);
}

.btn-outline {
  background: var(--bg-surface);
  border: 1.5px solid var(--border);
  color: var(--text-primary);
  font-weight: 700;
  transition: all 0.22s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.btn-outline:hover {
  transform: translateY(-2px);
  background: rgba(99, 102, 241, 0.08);
  border-color: var(--primary);
  color: var(--primary);
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.15);
}

.btn-gradient-amber {
  background: var(--grad-amber);
  color: #ffffff !important;
  box-shadow: 0 4px 14px rgba(245, 158, 11, 0.3);
}
.btn-gradient-amber:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(245, 158, 11, 0.45);
}

.btn-gradient-emerald {
  background: var(--grad-emerald);
  color: #ffffff !important;
  box-shadow: 0 4px 14px rgba(16, 185, 129, 0.3);
}
.btn-gradient-emerald:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(16, 185, 129, 0.45);
}

/* 10. Filter Bar Pills (.filter-pills-bar) */
.filter-pills-bar {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  overflow-x: auto;
  padding-bottom: 0.65rem;
  margin-bottom: 1.25rem;
  scrollbar-width: none;
}
.filter-pills-bar::-webkit-scrollbar {
  display: none;
}
.filter-pill {
  padding: 0.42rem 1rem;
  border-radius: 9999px;
  font-size: 0.82rem;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
  background: var(--bg-surface);
  color: var(--text-secondary);
  border: 1.5px solid var(--border);
  transition: all 0.22s cubic-bezier(0.34, 1.56, 0.64, 1);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.03);
}
.filter-pill:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(99, 102, 241, 0.15);
}
.filter-pill.active {
  background: var(--grad-primary);
  color: #ffffff !important;
  border-color: transparent;
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.35);
}

/* 11. Staggered Animations for Elements */
.animate-in {
  animation: fadeInUp 0.45s cubic-bezier(0.16, 1, 0.3, 1) both;
}

/* 12. Search Overlay Modern Glass & Animation */
.search-overlay {
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(15, 23, 42, 0.65);
}

.search-box {
  border: 1.5px solid rgba(99, 102, 241, 0.3);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.35), 0 0 30px rgba(99, 102, 241, 0.2);
  border-radius: var(--radius-xl);
}

.search-result-item {
  transition: all 0.2s ease;
  border-radius: var(--radius-md);
  margin: 0.25rem 0.5rem;
  padding: 0.65rem 0.85rem !important;
}

.search-result-item:hover {
  background: rgba(99, 102, 241, 0.08) !important;
  transform: translateX(4px);
}

.popular-term-btn {
  transition: all 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.popular-term-btn:hover {
  transform: translateY(-2px);
  border-color: var(--primary) !important;
  color: var(--primary) !important;
  background: rgba(99, 102, 241, 0.1) !important;
}

/* ============================================================
   13. FULL-WIDTH HERO STATS COUNTER BAR WITH CIRCULAR BADGES
   ============================================================ */
.hero-stats-wrapper {
  position: relative;
  margin-top: 0;
  margin-bottom: 3rem;
  z-index: 10;
  width: 100%;
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  border-left: none;
  border-right: none;
  border-radius: 0 !important;
  box-shadow: 0 4px 20px -5px rgba(15, 23, 42, 0.05), 0 2px 8px -2px rgba(99, 102, 241, 0.04);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

[data-theme="dark"] .hero-stats-wrapper {
  background: rgba(17, 24, 39, 0.95);
  border-top-color: rgba(255, 255, 255, 0.08);
  border-bottom-color: rgba(255, 255, 255, 0.08);
  box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
}

.hero-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  background: transparent;
  border: none;
  border-radius: 0 !important;
  padding: 1.5rem 0;
  box-shadow: none;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  min-height: 100px;
  align-items: center;
  width: 100%;
}

[data-theme="dark"] .hero-stats-grid {
  background: transparent;
  border-color: transparent;
  box-shadow: none;
}

.hero-stat-card {
  display: flex;
  align-items: center;
  gap: 1.15rem;
  padding: 0.75rem 1rem;
  border-radius: 0;
  transition: transform 0.25s var(--ease-spring), background 0.25s ease, box-shadow 0.25s ease;
  position: relative;
}

.hero-stat-card:hover {
  transform: translateY(-3px);
  background: var(--bg-surface);
  box-shadow: var(--shadow-sm);
}

/* Circular Ring & Icon Container (Larger & Prominent) */
.stat-circle-wrap {
  position: relative;
  width: 58px;
  height: 58px;
  min-width: 58px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  flex-shrink: 0;
}

.stat-ring-svg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.stat-ring-bg {
  fill: none;
  stroke: var(--border);
  stroke-width: 3.5;
}

.stat-ring-progress {
  fill: none;
  stroke-width: 3.8;
  stroke-linecap: round;
  transition: stroke-dashoffset 1.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.stat-circle-icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  z-index: 2;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.hero-stat-card:hover .stat-circle-icon {
  transform: scale(1.12) rotate(4deg);
}

/* Gradient Variants for Circular Badges */
.stat-grad-indigo .stat-ring-progress { stroke: #6366f1; }
.stat-grad-indigo .stat-circle-icon {
  background: rgba(99, 102, 241, 0.15);
  color: #6366f1;
  box-shadow: 0 0 16px rgba(99, 102, 241, 0.28);
}

.stat-grad-emerald .stat-ring-progress { stroke: #10b981; }
.stat-grad-emerald .stat-circle-icon {
  background: rgba(16, 185, 129, 0.15);
  color: #10b981;
  box-shadow: 0 0 16px rgba(16, 185, 129, 0.28);
}

.stat-grad-amber .stat-ring-progress { stroke: #f59e0b; }
.stat-grad-amber .stat-circle-icon {
  background: rgba(245, 158, 11, 0.15);
  color: #f59e0b;
  box-shadow: 0 0 16px rgba(245, 158, 11, 0.28);
}

.stat-grad-cyan .stat-ring-progress { stroke: #06b6d4; }
.stat-grad-cyan .stat-circle-icon {
  background: rgba(6, 182, 212, 0.15);
  color: #06b6d4;
  box-shadow: 0 0 16px rgba(6, 182, 212, 0.28);
}

/* Stat Details */
.stat-info {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.stat-number-wrap {
  display: flex;
  align-items: baseline;
  gap: 0.15rem;
}

.stat-counter-val {
  font-size: 1.75rem;
  font-weight: 900;
  color: var(--text-primary);
  line-height: 1.1;
  letter-spacing: -0.025em;
  font-variant-numeric: tabular-nums;
}

.stat-plus {
  font-size: 1.35rem;
  font-weight: 900;
  color: var(--primary);
}

.stat-counter-label {
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--text-muted);
  white-space: nowrap;
  margin-top: 0.2rem;
  letter-spacing: 0.01em;
}

/* Responsive Stat Bar */
@media (max-width: 1024px) {
  .hero-stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
    padding: 1.5rem 0;
  }
}

@media (max-width: 640px) {
  .hero-stats-wrapper {
    margin-top: 0;
    margin-bottom: 2rem;
    border-radius: 0 !important;
  }
  .hero-stats-grid {
    grid-template-columns: 1fr 1fr;
    gap: 0.85rem;
    padding: 1.15rem 0;
    border-radius: 0 !important;
  }
  .hero-stat-card {
    gap: 0.65rem;
    padding: 0.4rem;
    border-radius: 0;
  }
  .stat-circle-wrap {
    width: 46px;
    height: 46px;
    min-width: 46px;
  }
  .stat-circle-icon {
    width: 34px;
    height: 34px;
    font-size: 1.05rem;
  }
  .stat-counter-val {
    font-size: 1.25rem;
  }
  .stat-plus {
    font-size: 1.05rem;
  }
  .stat-counter-label {
    font-size: 0.72rem;
  }
}