/* ============================================
   2026 Assessment Redesign Framework
   Design System & Stylesheet
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Primary palette */
  --color-primary: #1e3a5f;
  --color-primary-light: #2c5282;
  --color-primary-dark: #132842;

  /* Accent */
  --color-accent: #b8860b;
  --color-accent-light: #d4a437;
  --color-accent-dark: #9a7009;

  /* Track colors */
  --color-track1: #2563eb;
  --color-track1-bg: #eff6ff;
  --color-track1-border: #bfdbfe;
  --color-track2: #16a34a;
  --color-track2-bg: #f0fdf4;
  --color-track2-border: #bbf7d0;

  /* Risk colors */
  --color-risk-high: #dc2626;
  --color-risk-high-bg: #fef2f2;
  --color-risk-medium: #d97706;
  --color-risk-medium-bg: #fffbeb;
  --color-risk-low: #16a34a;
  --color-risk-low-bg: #f0fdf4;

  /* Neutrals */
  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --color-border: #e2e8f0;
  --color-border-light: #f1f5f9;
  --color-text: #1e293b;
  --color-text-secondary: #475569;
  --color-text-muted: #94a3b8;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-serif: 'Georgia', 'Times New Roman', serif;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Sizing */
  --max-width: 1200px;
  --content-width: 800px;
  --sidebar-width: 260px;

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

  /* Borders */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  /* Transitions */
  --transition: 150ms ease;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

a:hover {
  color: var(--color-accent);
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.3;
  color: var(--color-primary);
  font-weight: 700;
}

h1 {
  font-size: 2.25rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 1.75rem;
  letter-spacing: -0.01em;
  margin-top: var(--space-3xl);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-border);
}

h3 {
  font-size: 1.35rem;
  margin-top: var(--space-2xl);
  margin-bottom: var(--space-md);
}

h4 {
  font-size: 1.1rem;
  margin-top: var(--space-xl);
  margin-bottom: var(--space-sm);
}

p {
  margin-bottom: var(--space-md);
}

ul, ol {
  margin-bottom: var(--space-md);
  padding-left: var(--space-xl);
}

li {
  margin-bottom: var(--space-sm);
}

li::marker {
  color: var(--color-accent);
}

blockquote {
  border-left: 4px solid var(--color-accent);
  padding: var(--space-md) var(--space-lg);
  margin: var(--space-xl) 0;
  background: var(--color-border-light);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic;
  color: var(--color-text-secondary);
}

blockquote cite {
  display: block;
  margin-top: var(--space-sm);
  font-style: normal;
  font-weight: 600;
  color: var(--color-primary);
  font-size: 0.9rem;
}

strong {
  font-weight: 600;
}

/* --- Header & Navigation --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-primary-dark);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(8px);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-xl);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.site-logo {
  font-size: 0.8rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.85);
  white-space: nowrap;
  letter-spacing: 0.01em;
}

.site-logo span {
  color: var(--color-accent-light);
}

.mobile-title {
  display: none;
  font-size: 0.85rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.9);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  flex: 1;
  min-width: 0;
}

/* Hamburger */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #ffffff;
  margin: 5px 0;
  transition: var(--transition);
  border-radius: 2px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.main-nav a {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.875rem;
  font-weight: 500;
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  white-space: nowrap;
}

.main-nav a:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.1);
}

.main-nav a.active {
  color: var(--color-accent-light);
  background: rgba(255, 255, 255, 0.15);
}

/* --- Page Layout --- */
.page-wrapper {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-xl);
  display: grid;
  grid-template-columns: 1fr var(--sidebar-width);
  gap: var(--space-3xl);
}

.page-wrapper.full-width {
  grid-template-columns: 1fr;
}

.page-content {
  min-width: 0;
}

/* --- Sidebar --- */
.page-sidebar {
  position: relative;
}

.sidebar-nav {
  position: sticky;
  top: 84px;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  border: 1px solid var(--color-border);
}

.sidebar-nav h4 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
  margin: 0 0 var(--space-md) 0;
}

.sidebar-nav ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.sidebar-nav li {
  margin-bottom: 0;
}

.sidebar-nav a {
  display: block;
  padding: var(--space-xs) var(--space-sm);
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  transition: all var(--transition);
}

.sidebar-nav a:hover {
  color: var(--color-primary);
  border-left-color: var(--color-accent);
  background: var(--color-border-light);
}

/* --- Hero Section --- */
.hero {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 50%, var(--color-primary-light) 100%);
  color: #ffffff;
  padding: var(--space-3xl) var(--space-xl);
  text-align: center;
}

.hero-inner {
  max-width: var(--content-width);
  margin: 0 auto;
}

.hero h1 {
  color: #ffffff;
  font-size: 2.75rem;
  margin-bottom: var(--space-sm);
}

.hero .subtitle {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: var(--space-sm);
  font-weight: 400;
}

.hero .author {
  font-size: 1rem;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: var(--space-xl);
}

.hero p {
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.9);
  line-height: 1.8;
  max-width: 640px;
  margin: 0 auto var(--space-xl);
}

.hero-buttons {
  display: flex;
  justify-content: center;
  gap: var(--space-md);
  flex-wrap: wrap;
}

.hero-buttons .btn {
  min-width: 200px;
  justify-content: center;
}

.author-profile {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-lg);
  margin-bottom: var(--space-xl);
}

.author-photo {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  border: 3px solid rgba(255, 255, 255, 0.3);
  object-fit: cover;
}

.author-info {
  text-align: left;
}

.author-info .author-name {
  font-size: 1.15rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 0.1em;
}

.author-info .author-title {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 0.4em;
}

.author-social {
  display: flex;
  gap: var(--space-md);
}

.author-social a {
  display: inline-flex;
  align-items: center;
  gap: 0.35em;
  color: rgba(255, 255, 255, 0.65);
  font-size: 0.85rem;
  transition: color var(--transition);
}

.author-social a:hover {
  color: #ffffff;
}

.author-social svg {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

/* --- Page Hero (smaller, for inner pages) --- */
.page-hero {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
  color: #ffffff;
  padding: var(--space-2xl) var(--space-xl);
}

.page-hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.page-hero h1 {
  color: #ffffff;
  font-size: 2rem;
  margin-bottom: var(--space-sm);
}

.page-hero p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 1.05rem;
  max-width: 640px;
}

.breadcrumb {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
  margin-bottom: var(--space-md);
}

.breadcrumb a {
  color: rgba(255, 255, 255, 0.6);
}

.breadcrumb a:hover {
  color: #ffffff;
}

/* --- Cards --- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-lg);
  margin: var(--space-xl) 0;
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-xl);
  transition: all var(--transition);
}

a.card {
  display: block;
  text-decoration: none;
  color: inherit;
}

a.card:hover {
  color: inherit;
}

.card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary-light);
}

.card h3 {
  margin-top: 0;
  font-size: 1.15rem;
}

.card p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  margin-bottom: var(--space-md);
}

.card .card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  font-size: 1.5rem;
  margin-bottom: var(--space-md);
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-primary-light);
}

.card-link::after {
  content: '\2192';
  transition: transform var(--transition);
}

.card:hover .card-link::after {
  transform: translateX(3px);
}

/* --- Numbered Cards --- */
.numbered-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-xl);
  position: relative;
  counter-increment: card-counter;
}

.numbered-card::before {
  content: counter(card-counter);
  position: absolute;
  top: var(--space-lg);
  right: var(--space-lg);
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-border);
  line-height: 1;
}

.numbered-list {
  counter-reset: card-counter;
}

.numbered-card h3 {
  margin-top: 0;
  padding-right: 2.5rem;
}

/* --- Callout Boxes --- */
.callout {
  padding: var(--space-lg);
  border-radius: var(--radius-md);
  margin: var(--space-xl) 0;
  border-left: 4px solid;
}

.callout-info {
  background: #eff6ff;
  border-color: var(--color-track1);
}

.callout-success {
  background: #f0fdf4;
  border-color: var(--color-track2);
}

.callout-warning {
  background: #fffbeb;
  border-color: #d97706;
}

.callout-important {
  background: #fef2f2;
  border-color: #dc2626;
}

.callout h4 {
  margin-top: 0;
  margin-bottom: var(--space-sm);
}

.callout p:last-child {
  margin-bottom: 0;
}

/* --- Badges --- */
.badge {
  display: inline-block;
  padding: 0.15em 0.65em;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 100px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.badge-track1 {
  background: var(--color-track1-bg);
  color: var(--color-track1);
  border: 1px solid var(--color-track1-border);
}

.badge-track2 {
  background: var(--color-track2-bg);
  color: var(--color-track2);
  border: 1px solid var(--color-track2-border);
}

.badge-high {
  background: var(--color-risk-high-bg);
  color: var(--color-risk-high);
  border: 1px solid #fecaca;
}

.badge-medium {
  background: var(--color-risk-medium-bg);
  color: var(--color-risk-medium);
  border: 1px solid #fde68a;
}

.badge-low {
  background: var(--color-risk-low-bg);
  color: var(--color-risk-low);
  border: 1px solid #bbf7d0;
}

/* --- Tables --- */
.table-wrapper {
  overflow-x: auto;
  margin: var(--space-xl) 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  border-bottom: none;
}

thead {
  background: var(--color-primary);
  color: #ffffff;
}

th {
  padding: var(--space-md) var(--space-lg);
  text-align: left;
  font-weight: 600;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

td {
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
}

tbody tr:last-child td {
  border-bottom: none;
}

tbody tr:nth-child(even) {
  background: var(--color-border-light);
}

tbody tr:hover {
  background: #e9eef4;
}

td ul {
  margin: 0;
  padding-left: var(--space-lg);
}

td ul li {
  margin-bottom: var(--space-xs);
}

/* --- Principle Cards --- */
.principle-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-xl);
  margin: var(--space-lg) 0;
  border-top: 4px solid var(--color-primary);
}

.principle-card h3 {
  margin-top: 0;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.principle-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: var(--color-primary);
  color: #ffffff;
  border-radius: 50%;
  font-size: 0.85rem;
  font-weight: 700;
  flex-shrink: 0;
}

/* --- Track Comparison --- */
.track-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
  margin: var(--space-xl) 0;
}

.track-box {
  padding: var(--space-xl);
  border-radius: var(--radius-md);
  border: 2px solid;
}

.track-box.track1 {
  background: var(--color-track1-bg);
  border-color: var(--color-track1);
}

.track-box.track2 {
  background: var(--color-track2-bg);
  border-color: var(--color-track2);
}

.track-box h3 {
  margin-top: 0;
}

.track-box.track1 h3 {
  color: var(--color-track1);
}

.track-box.track2 h3 {
  color: var(--color-track2);
}

/* --- Tip Cards --- */
.tip-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-xl);
  margin: var(--space-lg) 0;
  display: flex;
  gap: var(--space-lg);
}

.tip-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  min-width: 48px;
  height: 48px;
  background: var(--color-accent);
  color: #ffffff;
  border-radius: 50%;
  font-size: 1.25rem;
  font-weight: 800;
  flex-shrink: 0;
  aspect-ratio: 1;
}

.tip-content h3 {
  margin-top: 0;
  font-size: 1.1rem;
}

.tip-content p:last-child {
  margin-bottom: 0;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.65em 1.5em;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
}

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

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

.btn-outline {
  background: transparent;
  color: #ffffff;
  border: 2px solid rgba(255, 255, 255, 0.5);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: #ffffff;
  color: #ffffff;
}

/* --- Section Divider --- */
.section-intro {
  font-size: 1.05rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-xl);
  line-height: 1.8;
}

/* --- Footer --- */
.site-footer {
  background: var(--color-primary-dark);
  color: rgba(255, 255, 255, 0.7);
  padding: var(--space-2xl) var(--space-xl);
  margin-top: var(--space-3xl);
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: var(--space-2xl);
}

.footer-col h4 {
  color: #ffffff;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-top: 0;
  margin-bottom: var(--space-md);
}

.footer-col ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-col li {
  margin-bottom: var(--space-xs);
}

.footer-col a {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.9rem;
}

.footer-col a:hover {
  color: #ffffff;
}

.footer-bottom {
  max-width: var(--max-width);
  margin: var(--space-xl) auto 0;
  padding-top: var(--space-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.4);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-lg);
}

.footer-bottom p {
  margin: 0;
  text-align: right;
}

.footer-licence {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex-shrink: 0;
}

.footer-licence img {
  height: 22px;
  opacity: 0.6;
  transition: opacity var(--transition);
}

.footer-licence:hover img {
  opacity: 0.9;
}

.footer-licence span {
  color: rgba(255, 255, 255, 0.4);
  font-size: 0.8rem;
  white-space: nowrap;
}

.footer-bottom a {
  color: rgba(255, 255, 255, 0.5);
}

.footer-bottom a:hover {
  color: rgba(255, 255, 255, 0.8);
}

/* --- Next/Prev Navigation --- */
.page-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--space-lg);
  margin-top: var(--space-3xl);
  padding-top: var(--space-xl);
  border-top: 2px solid var(--color-border);
}

.page-nav a {
  display: flex;
  flex-direction: column;
  padding: var(--space-md) var(--space-lg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition);
  flex: 1;
  max-width: 50%;
}

.page-nav a:hover {
  border-color: var(--color-primary);
  background: var(--color-border-light);
}

.page-nav .label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xs);
}

.page-nav .title {
  font-weight: 600;
  color: var(--color-primary);
}

.page-nav .next {
  text-align: right;
  margin-left: auto;
}

/* --- Glossary --- */
.glossary-list {
  margin: 0;
  padding: 0;
}

.glossary-list dt {
  padding-top: var(--space-md);
  margin-top: var(--space-md);
  border-top: 1px solid var(--color-border);
  font-size: 1.05rem;
}

.glossary-list dt:first-child {
  border-top: none;
  margin-top: 0;
  padding-top: 0;
}

.glossary-list dd {
  margin-left: var(--space-lg);
  margin-bottom: var(--space-sm);
  color: var(--color-text-secondary);
  font-size: 0.95rem;
}

/* --- Lightbox --- */
.lightbox-img {
  cursor: pointer;
  transition: opacity var(--transition);
}

.lightbox-img:hover {
  opacity: 0.85;
}

.lightbox-overlay {
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(0, 0, 0, 0.85);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  padding: var(--space-xl);
  opacity: 0;
  transition: opacity 0.25s ease;
}

.lightbox-overlay.visible {
  opacity: 1;
}

.lightbox-overlay img {
  max-width: 100%;
  max-height: 90vh;
  border-radius: var(--radius-md);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

/* --- Download Items --- */
.download-item {
  margin: var(--space-lg) 0;
}

.download-link {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-lg);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: inherit;
  transition: all var(--transition);
}

.download-link:hover {
  border-color: var(--color-primary-light);
  box-shadow: var(--shadow-md);
  color: inherit;
}

.download-icon {
  flex-shrink: 0;
}

.download-info {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.download-name {
  font-weight: 600;
  color: var(--color-primary);
  font-size: 0.95rem;
}

.download-meta {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

/* --- Utility --- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* --- Responsive --- */
@media (max-width: 960px) {
  .page-wrapper {
    grid-template-columns: 1fr;
    padding: var(--space-xl) var(--space-lg);
  }

  .page-sidebar {
    order: -1;
  }

  .sidebar-nav {
    position: static;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-md);
  }

  .footer-bottom p {
    text-align: left;
  }

  .track-comparison {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--color-primary-dark);
    flex-direction: column;
    padding: var(--space-md);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: var(--shadow-lg);
  }

  .main-nav.open {
    display: flex;
  }

  .main-nav a {
    padding: var(--space-md);
    width: 100%;
  }

  .mobile-title {
    display: block;
  }

  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }

  .hero-buttons .btn {
    width: 100%;
    max-width: 280px;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .hero .subtitle {
    font-size: 1.05rem;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .page-hero h1 {
    font-size: 1.6rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .tip-card {
    flex-direction: column;
  }

  .page-nav {
    flex-direction: column;
  }

  .page-nav a {
    max-width: 100%;
    width: 100%;
  }

  .table-wrapper {
    font-size: 0.85rem;
  }

  th, td {
    padding: var(--space-sm) var(--space-md);
  }
}

/* --- Print Styles --- */
@media print {
  .site-header,
  .site-footer,
  .page-sidebar,
  .page-nav,
  .nav-toggle {
    display: none !important;
  }

  .page-wrapper {
    grid-template-columns: 1fr;
    padding: 0;
  }

  body {
    font-size: 11pt;
    line-height: 1.5;
    color: #000;
    background: #fff;
  }

  h2 {
    page-break-after: avoid;
    border-bottom-color: #ccc;
  }

  .card, .principle-card, .callout, .tip-card, .numbered-card, .track-box {
    break-inside: avoid;
    border-color: #ccc;
    box-shadow: none;
  }

  a {
    color: #000;
    text-decoration: underline;
  }

  table {
    font-size: 9pt;
  }

  thead {
    background: #eee;
    color: #000;
  }
}

/* --- Scroll-to-top Button --- */
.scroll-top {
  position: fixed;
  bottom: var(--space-xl);
  right: var(--space-xl);
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-primary);
  color: #ffffff;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.25s ease, transform 0.25s ease, background 0.15s ease;
  pointer-events: none;
  z-index: 90;
}

.scroll-top.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.scroll-top:hover {
  background: var(--color-accent);
}

/* --- Sidebar Active Highlight --- */
.sidebar-nav a.sidebar-active {
  color: var(--color-primary);
  border-left-color: var(--color-accent);
  background: var(--color-border-light);
  font-weight: 600;
}

/* --- Accessibility --- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}

*:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 2px;
}