/* ============================================================
   WEBBOOK.CSS — Bio-Digital Ocean Design System
   ============================================================ */

/* ── Custom Properties ────────────────────────────────────── */
:root {
  /* Palette */
  --bg-deep:    #050f17;
  --bg-mid:     #0a1e2e;
  --bg-card:    #0d2233;
  --teal:       #00c8b4;
  --blue:       #4a9eff;
  --aqua:       #7fffd4;
  --amber:      #ffb84d;
  --pink:       #ff7eb3;
  --violet:     #a78bfa;
  --text-main:  #cce8f0;
  --text-muted: #7a9fb5;
  --text-dim:   #4a6e82;
  --border:     rgba(0, 200, 180, 0.15);

  /* Typography */
  --font-body:    'Georgia', 'Times New Roman', serif;
  --font-display: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  --font-mono:    'Fira Mono', 'Consolas', monospace;

  /* Spacing */
  --space-xs:  0.4rem;
  --space-sm:  0.8rem;
  --space-md:  1.6rem;
  --space-lg:  2.8rem;
  --space-xl:  4.8rem;

  /* Radii */
  --radius-sm:  6px;
  --radius-md:  14px;
  --radius-lg:  28px;
  --radius-full: 9999px;

  /* Transitions */
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-out:    cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);

  /* Layout */
  --content-max: 72ch;
  --content-wide: 1100px;
  --header-h: 60px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 18px;
}

/* ── Scrollbar ────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-deep); }
::-webkit-scrollbar-thumb {
  background: var(--teal);
  border-radius: var(--radius-full);
  opacity: 0.6;
}

::selection {
  background: rgba(0, 200, 180, 0.3);
  color: #fff;
}

/* ── Body ─────────────────────────────────────────────────── */
body {
  background-color: var(--bg-deep);
  color: var(--text-main);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.8;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

/* ── Background Orbs ──────────────────────────────────────── */
.bg-orb {
  position: fixed;
  border-radius: 50%;
  filter: blur(80px);
  pointer-events: none;
  z-index: 0;
  animation: breathe 8s ease-in-out infinite;
}

.bg-orb-1 {
  width: 500px;
  height: 500px;
  top: -120px;
  left: -120px;
  background: radial-gradient(circle, rgba(0,200,180,0.12) 0%, transparent 70%);
  animation-duration: 9s;
}

.bg-orb-2 {
  width: 400px;
  height: 400px;
  top: 40%;
  right: -100px;
  background: radial-gradient(circle, rgba(74,158,255,0.10) 0%, transparent 70%);
  animation-duration: 12s;
  animation-delay: -4s;
}

.bg-orb-3 {
  width: 350px;
  height: 350px;
  bottom: 10%;
  left: 20%;
  background: radial-gradient(circle, rgba(167,139,250,0.08) 0%, transparent 70%);
  animation-duration: 15s;
  animation-delay: -8s;
}

/* ── Progress Bar ─────────────────────────────────────────── */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--teal), var(--blue), var(--aqua));
  z-index: 200;
  transition: width 0.1s linear;
  box-shadow: 0 0 10px rgba(0,200,180,0.6);
}

/* ── Site Header ──────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  padding: 0 var(--space-lg);
  background: rgba(5, 15, 23, 0.75);
  backdrop-filter: blur(16px) saturate(160%);
  -webkit-backdrop-filter: blur(16px) saturate(160%);
  border-bottom: 1px solid var(--border);
}

.site-header a {
  text-decoration: none;
  color: var(--text-muted);
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transition: color 0.25s var(--ease-out);
}

.site-header a:hover { color: var(--teal); }

.header-book-title {
  margin-left: auto;
  color: var(--text-dim);
  font-size: 0.72rem;
  font-family: var(--font-display);
  letter-spacing: 0.06em;
}

/* ── Chapter Hero ─────────────────────────────────────────── */
.chapter-hero {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xl);
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: var(--space-xl) var(--space-lg) var(--space-lg);
  flex-wrap: wrap;
}

.chapter-hero-text {
  flex: 1 1 340px;
  max-width: 520px;
}

.chapter-number {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--teal);
  background: rgba(0, 200, 180, 0.08);
  border: 1px solid rgba(0, 200, 180, 0.25);
  padding: 0.3em 0.9em;
  border-radius: var(--radius-full);
  margin-bottom: var(--space-md);
}

.chapter-title {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 700;
  line-height: 1.15;
  color: #fff;
  margin-bottom: var(--space-sm);
  letter-spacing: -0.02em;
}

.chapter-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.65;
  font-style: italic;
}

.chapter-hero-svg {
  flex: 0 0 auto;
  width: 340px;
  height: 340px;
  position: relative;
}

.chapter-hero-svg svg {
  width: 100%;
  height: 100%;
  overflow: visible;
}

/* ── Content Wrapper ──────────────────────────────────────── */
.content-wrapper {
  position: relative;
  z-index: 1;
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: 0 var(--space-lg) var(--space-xl);
}

/* ── Reading Sections ─────────────────────────────────────── */
.reading-section {
  max-width: var(--content-max);
  margin: 0 auto var(--space-xl);
}

.reading-section h2 {
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 2.5vw, 1.6rem);
  font-weight: 600;
  color: #fff;
  margin-bottom: var(--space-md);
  margin-top: var(--space-xl);
  padding-top: var(--space-md);
  border-top: 1px solid var(--border);
  letter-spacing: -0.01em;
}

.reading-section h3 {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--aqua);
  margin-bottom: var(--space-sm);
  margin-top: var(--space-lg);
}

.reading-section p {
  margin-bottom: var(--space-md);
  color: var(--text-main);
}

.reading-section p + p {
  margin-top: -0.4rem;
}

.reading-section ul,
.reading-section ol {
  margin: var(--space-sm) 0 var(--space-md) var(--space-lg);
  color: var(--text-main);
}

.reading-section li {
  margin-bottom: 0.4em;
}

.reading-section strong {
  color: #e8f4f8;
  font-weight: 600;
}

.reading-section em {
  color: var(--aqua);
  font-style: italic;
}

/* ── Pull Quote ───────────────────────────────────────────── */
.pullquote {
  position: relative;
  margin: var(--space-xl) 0;
  padding: var(--space-lg) var(--space-lg) var(--space-lg) calc(var(--space-lg) + 4px);
  border-left: 4px solid var(--teal);
  background: linear-gradient(135deg,
    rgba(0,200,180,0.05) 0%,
    rgba(74,158,255,0.04) 100%
  );
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.pullquote::before {
  content: '"';
  position: absolute;
  top: -0.3em;
  left: var(--space-md);
  font-size: 5rem;
  font-family: var(--font-display);
  color: rgba(0,200,180,0.18);
  line-height: 1;
  pointer-events: none;
}

.pullquote p {
  font-size: 1.15rem;
  line-height: 1.7;
  color: var(--text-main);
  font-style: italic;
  margin: 0;
}

.pullquote cite {
  display: block;
  margin-top: var(--space-sm);
  font-size: 0.82rem;
  font-style: normal;
  color: var(--teal);
  font-family: var(--font-display);
  letter-spacing: 0.05em;
}

/* ── Concept Box ──────────────────────────────────────────── */
.concept-box {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  margin: var(--space-lg) 0;
  position: relative;
  overflow: hidden;
}

.concept-box::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg,
    rgba(0,200,180,0.05) 0%,
    transparent 60%
  );
  pointer-events: none;
}

.concept-box h3 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--teal);
  margin-bottom: var(--space-md);
  margin-top: 0;
}

.concept-box ul {
  margin: 0;
  padding-left: var(--space-md);
  list-style: none;
}

.concept-box ul li {
  padding: 0.3em 0;
  padding-left: var(--space-sm);
  position: relative;
  color: var(--text-main);
}

.concept-box ul li::before {
  content: '→';
  position: absolute;
  left: -1.2em;
  color: var(--teal);
  font-weight: bold;
}

.concept-box p {
  color: var(--text-main);
  margin-bottom: var(--space-sm);
}

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

/* ── Mismatch Table ───────────────────────────────────────── */
.mismatch-table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-lg) 0;
  font-family: var(--font-display);
  font-size: 0.9rem;
  border-radius: var(--radius-md);
  overflow: hidden;
}

.mismatch-table thead {
  background: rgba(0, 200, 180, 0.12);
}

.mismatch-table thead th {
  padding: var(--space-sm) var(--space-md);
  text-align: left;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--teal);
  border-bottom: 1px solid var(--border);
}

.mismatch-table tbody tr {
  border-bottom: 1px solid rgba(0,200,180,0.06);
  transition: background 0.2s ease;
}

.mismatch-table tbody tr:last-child { border-bottom: none; }

.mismatch-table tbody tr:hover {
  background: rgba(0,200,180,0.04);
}

.mismatch-table td {
  padding: 0.75rem var(--space-md);
  vertical-align: top;
  color: var(--text-main);
  line-height: 1.55;
}

.mismatch-table td:first-child {
  color: var(--aqua);
  font-weight: 600;
  white-space: nowrap;
}

.mismatch-table td strong {
  color: var(--amber);
}

/* ── Chapter Navigation ───────────────────────────────────── */
.chapter-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  max-width: var(--content-max);
  margin: var(--space-xl) auto 0;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--border);
}

a.nav-card {
  display: flex;
  flex-direction: column;
  padding: var(--space-md);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: border-color 0.25s var(--ease-out),
              transform 0.3s var(--ease-spring),
              box-shadow 0.25s var(--ease-out);
}

a.nav-card:hover {
  border-color: rgba(0,200,180,0.45);
  transform: translateY(-3px);
  box-shadow: 0 12px 32px rgba(0,0,0,0.35),
              0 0 0 1px rgba(0,200,180,0.15);
}

.nav-card-label {
  font-family: var(--font-display);
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--text-dim);
  margin-bottom: 0.35em;
}

.nav-card-title {
  font-family: var(--font-display);
  font-size: 0.95rem;
  color: var(--text-main);
  font-weight: 500;
}

a.nav-card[rel="next"] .nav-card-label { text-align: right; }
a.nav-card[rel="next"] { text-align: right; }

/* ── TOC Index Page ───────────────────────────────────────── */
.toc-hero {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: var(--space-xl) var(--space-lg) var(--space-lg);
}

.toc-hero canvas {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

.toc-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 3.6rem);
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-sm);
  line-height: 1.1;
}

.toc-subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 54ch;
  margin: 0 auto var(--space-lg);
}

.toc-orbital {
  width: 300px;
  height: 300px;
  margin: var(--space-lg) auto;
}

.toc-part {
  max-width: var(--content-wide);
  margin: 0 auto var(--space-xl);
  padding: 0 var(--space-lg);
}

.toc-part-title {
  font-family: var(--font-display);
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--teal);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--border);
}

.toc-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: var(--space-md);
}

.toc-card {
  display: block;
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-md) var(--space-md) var(--space-md) calc(var(--space-md) + 2px);
  text-decoration: none;
  overflow: hidden;
  transition: border-color 0.25s var(--ease-out),
              transform 0.3s var(--ease-spring),
              box-shadow 0.25s var(--ease-out);
}

.toc-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 100%;
  background: var(--card-color, var(--teal));
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
}

.toc-card:hover {
  border-color: rgba(0,200,180,0.35);
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(0,0,0,0.4);
}

.toc-card.unavailable {
  opacity: 0.45;
  pointer-events: none;
}

.toc-card-num {
  font-family: var(--font-display);
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--card-color, var(--teal));
  margin-bottom: 0.4em;
}

.toc-card-title {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
  line-height: 1.3;
  margin-bottom: 0.4em;
}

.toc-card-sub {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.45;
}

.toc-card-badge {
  display: inline-block;
  margin-top: var(--space-sm);
  font-family: var(--font-display);
  font-size: 0.64rem;
  padding: 0.2em 0.6em;
  border-radius: var(--radius-full);
  background: rgba(0,200,180,0.08);
  border: 1px solid rgba(0,200,180,0.2);
  color: var(--teal);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* TOC card color variants */
.card-c0  { --card-color: #00c8b4; }
.card-c1  { --card-color: #4a9eff; }
.card-c2  { --card-color: #a78bfa; }
.card-c3  { --card-color: #ffb84d; }
.card-c4  { --card-color: #ff7eb3; }
.card-c5  { --card-color: #7fffd4; }
.card-c6  { --card-color: #00c8b4; }
.card-c7  { --card-color: #4a9eff; }
.card-c8  { --card-color: #a78bfa; }
.card-c9  { --card-color: #ffb84d; }
.card-c10 { --card-color: #ff7eb3; }
.card-c11 { --card-color: #7fffd4; }

/* ── Scroll Animations ────────────────────────────────────── */
.animate-in {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s var(--ease-out),
              transform 0.7s var(--ease-out);
}

.animate-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger children */
.animate-in:nth-child(2) { transition-delay: 0.08s; }
.animate-in:nth-child(3) { transition-delay: 0.16s; }
.animate-in:nth-child(4) { transition-delay: 0.24s; }
.animate-in:nth-child(5) { transition-delay: 0.32s; }

/* ── Keyframe Animations ──────────────────────────────────── */
@keyframes breathe {
  0%, 100% { transform: scale(1) translate(0, 0); opacity: 0.7; }
  50%       { transform: scale(1.12) translate(8px, -12px); opacity: 1; }
}

@keyframes float-up {
  0%   { transform: translateY(0);    opacity: 0.6; }
  100% { transform: translateY(-30px); opacity: 0; }
}

@keyframes glow-pulse {
  0%, 100% { filter: drop-shadow(0 0 4px currentColor); }
  50%       { filter: drop-shadow(0 0 14px currentColor); }
}

@keyframes slide-in-up {
  from { opacity: 0; transform: translateY(40px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes particle-drift {
  0%   { transform: translate(0, 0) scale(1); opacity: 0.7; }
  50%  { transform: translate(6px, -16px) scale(1.15); opacity: 1; }
  100% { transform: translate(-4px, -30px) scale(0.8); opacity: 0; }
}

@keyframes wave {
  0%, 100% { d: path("M0,20 Q30,5 60,20 Q90,35 120,20"); }
  50%       { d: path("M0,20 Q30,35 60,20 Q90,5 120,20"); }
}

@keyframes node-pulse {
  0%, 100% { r: 5; opacity: 0.7; }
  50%       { r: 8; opacity: 1; }
}

@keyframes heartbeat {
  0%   { transform: scale(1); }
  14%  { transform: scale(1.18); }
  28%  { transform: scale(1); }
  42%  { transform: scale(1.1); }
  56%  { transform: scale(1); }
  100% { transform: scale(1); }
}

@keyframes shimmer {
  0%   { background-position: -400px 0; }
  100% { background-position: 400px 0; }
}

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

@keyframes orbit {
  from { transform: rotate(0deg) translateX(90px) rotate(0deg); }
  to   { transform: rotate(360deg) translateX(90px) rotate(-360deg); }
}

@keyframes fade-in-hero {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Chapter footer divider ───────────────────────────────── */
.chapter-end {
  text-align: center;
  padding: var(--space-xl) 0 var(--space-lg);
  color: var(--text-dim);
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.chapter-end::before {
  content: '';
  display: block;
  width: 60px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--teal), transparent);
  margin: 0 auto var(--space-md);
}

/* ── Inline highlights ────────────────────────────────────── */
mark {
  background: rgba(0,200,180,0.18);
  color: var(--aqua);
  padding: 0.1em 0.3em;
  border-radius: 3px;
}

code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: rgba(0,200,180,0.08);
  color: var(--aqua);
  padding: 0.15em 0.4em;
  border-radius: var(--radius-sm);
}

/* ── Responsive ───────────────────────────────────────────── */
@media (max-width: 900px) {
  html { font-size: 17px; }

  .chapter-hero {
    flex-direction: column-reverse;
    gap: var(--space-lg);
    padding: var(--space-lg) var(--space-md);
    text-align: center;
  }

  .chapter-hero-svg {
    width: 260px;
    height: 260px;
  }

  .content-wrapper {
    padding: 0 var(--space-md) var(--space-xl);
  }

  .site-header {
    padding: 0 var(--space-md);
  }

  .header-book-title { display: none; }
}

@media (max-width: 600px) {
  html { font-size: 16px; }

  .chapter-hero-svg {
    width: 200px;
    height: 200px;
  }

  .chapter-nav {
    grid-template-columns: 1fr;
  }

  .mismatch-table {
    font-size: 0.82rem;
  }

  .mismatch-table td {
    padding: 0.55rem var(--space-sm);
  }

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

  .bg-orb { display: none; }

  .pullquote {
    padding: var(--space-md);
  }

  .concept-box {
    padding: var(--space-md);
  }
}

/* ── Print ────────────────────────────────────────────────── */
@media print {
  .site-header,
  .progress-bar,
  .bg-orb,
  .chapter-nav { display: none; }

  body {
    background: #fff;
    color: #111;
    font-size: 11pt;
  }

  .chapter-hero-svg { display: none; }
}