/* ==============================================================
   QuizMaster — Core Design System & Global Styles
   Typography: Plus Jakarta Sans & Inter
   ============================================================== */

:root {
  /* Brand Theme Colors */
  --primary: #106f52;
  --primary-hover: #0a4f3a;
  --primary-light: #e6f4ee;
  --primary-gradient: linear-gradient(135deg, #106f52 0%, #08402f 100%);
  --accent: #f59e0b;
  --accent-light: #fef3c7;
  --accent-hover: #d97706;

  /* Neutrals & Surfaces */
  --bg-page: #f8fafc;
  --bg-card: #ffffff;
  --bg-card-hover: #f1f5f9;
  --bg-input: #ffffff;
  --border: #e2e8f0;
  --border-focus: #106f52;

  /* Typography */
  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  --font-heading: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;

  /* Feedback Colors */
  --success: #10b981;
  --success-bg: #ecfdf5;
  --danger: #ef4444;
  --danger-bg: #fef2f2;
  --info: #0284c7;
  --info-bg: #f0f9ff;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 14px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 12px 28px rgba(15, 23, 42, 0.12);
  --shadow-xl: 0 20px 40px rgba(15, 23, 42, 0.16);

  /* Radii */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
}

[data-theme="dark"] {
  --primary: #2dd4bf;
  --primary-hover: #14b8a6;
  --primary-light: #134e4a;
  --primary-gradient: linear-gradient(135deg, #14b8a6 0%, #0f766e 100%);
  --accent: #fbbf24;
  --accent-light: #78350f;

  --bg-page: #0f172a;
  --bg-card: #1e293b;
  --bg-card-hover: #334155;
  --bg-input: #1e293b;
  --border: #334155;
  --border-focus: #2dd4bf;

  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-light: #64748b;

  --success-bg: #064e3b;
  --danger-bg: #7f1d1d;
  --info-bg: #082f49;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 12px 28px rgba(0, 0, 0, 0.6);
}

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

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

body {
  font-family: var(--font-body);
  background-color: var(--bg-page);
  color: var(--text-main);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Layout Containers */
.site-container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Sticky Header on Standard Pages */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--bg-card);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}

/* CRITICAL UX RULE from Style Guide: Non-sticky header on play page */
body.is-quiz-arena .site-header {
  position: relative !important;
  top: auto !important;
  box-shadow: none !important;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  gap: 16px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-main);
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
}

.brand-icon {
  width: 38px;
  height: 38px;
  background: var(--primary-gradient);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  font-size: 1.25rem;
  box-shadow: 0 4px 10px rgba(16, 111, 82, 0.25);
}

.brand-badge {
  font-size: 0.65rem;
  font-weight: 700;
  background-color: var(--primary-light);
  color: var(--primary);
  padding: 2px 7px;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-left: 4px;
}

/* Desktop Navigation */
.desktop-nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.nav-link {
  text-decoration: none;
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.95rem;
  transition: color var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 6px;
}

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

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

/* Action Buttons */
.btn-icon {
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--text-main);
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
  touch-action: manipulation;
}

.btn-icon:hover {
  background-color: var(--bg-card-hover);
  border-color: var(--text-light);
}

.btn-menu-toggle {
  display: none;
}

/* Primary & Secondary Buttons */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--primary-gradient);
  color: #ffffff;
  border: none;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.95rem;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  box-shadow: 0 4px 12px rgba(16, 111, 82, 0.2);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), opacity var(--transition-fast);
  touch-action: manipulation;
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 18px rgba(16, 111, 82, 0.3);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: var(--bg-card);
  color: var(--text-main);
  border: 1px solid var(--border);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 12px 20px;
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  touch-action: manipulation;
}

.btn-secondary:hover {
  background-color: var(--bg-card-hover);
  border-color: var(--text-muted);
}

/* Hero Section */
.hero-section {
  padding: 48px 0 36px;
  text-align: center;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background-color: var(--primary-light);
  color: var(--primary);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  margin-bottom: 18px;
}

.hero-title {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
  color: var(--text-main);
}

.hero-title .highlight {
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 680px;
  margin: 0 auto 32px;
  line-height: 1.6;
}

/* Quick Search Bar */
.search-form {
  max-width: 580px;
  margin: 0 auto 28px;
  display: flex;
  background-color: var(--bg-card);
  border: 2px solid var(--border);
  border-radius: var(--radius-full);
  padding: 6px 8px 6px 20px;
  box-shadow: var(--shadow-md);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.search-form:focus-within {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 4px var(--primary-light);
}

.search-input {
  flex: 1;
  border: none;
  background: transparent;
  font-size: 1rem;
  color: var(--text-main);
  outline: none;
  font-family: var(--font-body);
}

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

.search-btn {
  background: var(--primary-gradient);
  color: #ffffff;
  border: none;
  padding: 10px 22px;
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  transition: opacity var(--transition-fast);
}

.search-btn:hover {
  opacity: 0.92;
}

/* Audience Filter Pills */
.filter-pills-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 36px;
}

.filter-pill {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.88rem;
  font-weight: 600;
  padding: 8px 18px;
  border-radius: var(--radius-full);
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  touch-action: manipulation;
}

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

.filter-pill.active {
  background-color: var(--primary);
  border-color: var(--primary);
  color: #ffffff;
}

/* Section Headers */
.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 24px;
  gap: 16px;
}

.section-title {
  font-family: var(--font-heading);
  font-size: 1.65rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
}

.section-link {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.section-link:hover {
  text-decoration: underline;
}

/* 48-Item Responsive Quiz Cards Gallery (Desktop 4 col, Tablet 3 col, Mobile 2 col) */
.quiz-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

@media (max-width: 1024px) {
  .quiz-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
  }
}

@media (max-width: 768px) {
  .quiz-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }
}

@media (max-width: 480px) {
  .quiz-grid {
    grid-template-columns: 1fr;
  }
}

/* Quiz Card UI */
.quiz-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 22px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), border-color var(--transition-fast);
  text-decoration: none;
  color: var(--text-main);
  position: relative;
  overflow: hidden;
}

.quiz-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.quiz-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
  gap: 8px;
}

.category-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--primary);
  background-color: var(--primary-light);
  padding: 4px 10px;
  border-radius: var(--radius-full);
}

.quiz-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.badge-beginner {
  background-color: #ecfdf5;
  color: #065f46;
}

.badge-intermediate {
  background-color: #fef3c7;
  color: #92400e;
}

.badge-advanced {
  background-color: #ffedd5;
  color: #9a3412;
}

.badge-master {
  background-color: #fee2e2;
  color: #991b1b;
}

.badge-kids {
  background-color: #f0fdf4;
  color: #166534;
}

.badge-teen {
  background-color: #eff6ff;
  color: #1e40af;
}

.badge-adult {
  background-color: #f5f3ff;
  color: #5b21b6;
}

.badge-senior {
  background-color: #fff7ed;
  color: #c2410c;
}

.quiz-card-title {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 10px;
  color: var(--text-main);
}

.quiz-card-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 18px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.quiz-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 14px;
  border-top: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--text-light);
}

.quiz-meta-item {
  display: flex;
  align-items: center;
  gap: 4px;
}

.quiz-play-link {
  font-weight: 700;
  color: var(--primary);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

/* Category Directory Cards (12 Pillars Grid) */
.category-pillars-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 48px;
}

@media (max-width: 1024px) {
  .category-pillars-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  .category-pillars-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .category-pillars-grid {
    grid-template-columns: 1fr;
  }
}

.category-pillar-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  text-decoration: none;
  color: var(--text-main);
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
}

.category-pillar-card:hover {
  transform: translateY(-3px);
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.pillar-icon {
  font-size: 2.2rem;
  margin-bottom: 14px;
  display: inline-block;
}

.pillar-title {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 800;
  margin-bottom: 8px;
}

.pillar-desc {
  font-size: 0.86rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 14px;
  flex: 1;
}

.pillar-meta {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* Daily Challenge Banner */
.daily-banner {
  background: var(--primary-gradient);
  color: #ffffff;
  border-radius: var(--radius-xl);
  padding: 36px 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 48px;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

.daily-banner::after {
  content: '⚡';
  position: absolute;
  right: -20px;
  bottom: -40px;
  font-size: 14rem;
  opacity: 0.08;
  pointer-events: none;
}

.daily-content h2 {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  font-weight: 800;
  margin-bottom: 10px;
}

.daily-content p {
  font-size: 1.05rem;
  opacity: 0.9;
  max-width: 620px;
}

.daily-action .btn-primary {
  background: var(--accent);
  color: #1a1a1a;
  box-shadow: 0 4px 14px rgba(245, 158, 11, 0.4);
}

.daily-action .btn-primary:hover {
  background: var(--accent-hover);
  color: #ffffff;
}

/* SEO Educational Content Section */
.seo-prose-section {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: 36px;
  margin-bottom: 48px;
  color: var(--text-main);
  line-height: 1.75;
}

.seo-prose-section h2, .seo-prose-section h3 {
  font-family: var(--font-heading);
  font-weight: 800;
  color: var(--text-main);
  margin: 20px 0 10px;
}

.seo-prose-section h2 { font-size: 1.45rem; }
.seo-prose-section h3 { font-size: 1.2rem; }

.seo-prose-section p {
  color: var(--text-muted);
  margin-bottom: 14px;
}

.seo-prose-section ul {
  padding-left: 24px;
  margin-bottom: 18px;
  color: var(--text-muted);
}

.seo-prose-section li {
  margin-bottom: 8px;
}

/* Ad Placement Containers */
.ad-container {
  width: 100%;
  margin: 24px auto;
  text-align: center;
  overflow: hidden;
}

.ad-test-box {
  background-color: var(--bg-card);
  border: 2px dashed var(--border);
  border-radius: var(--radius-md);
  padding: 24px;
  color: var(--text-light);
  font-size: 0.82rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Breadcrumbs */
.breadcrumbs {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
  padding: 16px 0;
}

.breadcrumbs a {
  color: var(--text-muted);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--primary);
  text-decoration: underline;
}

.breadcrumbs-separator {
  color: var(--text-light);
}

/* Site Footer */
.site-footer {
  margin-top: auto;
  background-color: var(--bg-card);
  border-top: 1px solid var(--border);
  padding: 48px 0 28px;
  color: var(--text-muted);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 36px;
  margin-bottom: 36px;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}

.footer-col h4 {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--text-main);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 14px;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.88rem;
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.85rem;
}

.footer-bottom a {
  color: var(--primary);
  text-decoration: none;
}

/* Mobile Navigation Drawer Architecture (Style Guide Rule: Outside Header) */
.mobile-nav-backdrop {
  position: fixed;
  inset: 0;
  background-color: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(4px);
  z-index: 1998;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

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

.mobile-nav-drawer {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  width: 300px;
  max-width: 85vw;
  background-color: var(--bg-card);
  z-index: 1999;
  box-shadow: -8px 0 24px rgba(0, 0, 0, 0.2);
  transform: translateX(100%);
  transition: transform var(--transition-normal);
  display: flex;
  flex-direction: column;
  padding: 24px;
  overflow-y: auto;
}

.mobile-nav-drawer.open {
  transform: translateX(0);
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.drawer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.drawer-links a {
  text-decoration: none;
  color: var(--text-main);
  font-weight: 700;
  font-size: 1.05rem;
  display: flex;
  align-items: center;
  gap: 12px;
}

@media (max-width: 768px) {
  .desktop-nav {
    display: none;
  }
  .btn-menu-toggle {
    display: flex;
  }
}