:root {
  --ai-bg: #071119;
  --ai-bg-elevated: rgba(13, 24, 35, 0.86);
  --ai-bg-panel: rgba(12, 22, 33, 0.86);
  --ai-surface: rgba(17, 31, 45, 0.92);
  --ai-surface-strong: rgba(20, 36, 52, 0.98);
  --ai-text: #eff5fb;
  --ai-text-muted: #9cafc7;
  --ai-border: rgba(122, 156, 191, 0.2);
  --ai-border-strong: rgba(111, 221, 231, 0.28);
  --ai-accent: #68e3e9;
  --ai-accent-strong: #49b8ff;
  --ai-accent-warm: #ffca62;
  --ai-shadow: 0 26px 80px rgba(2, 9, 18, 0.38);
  --ai-grid: rgba(104, 227, 233, 0.06);
  --ai-code: #0d1825;
  --ai-code-border: rgba(103, 159, 219, 0.18);
  --ai-radius-xl: 24px;
  --ai-radius-lg: 18px;
  --ai-radius-md: 12px;
  --ai-font: "Segoe UI", Inter, system-ui, sans-serif;
}

:root[data-theme="light"] {
  --ai-bg: #f3f8fc;
  --ai-bg-elevated: rgba(255, 255, 255, 0.92);
  --ai-bg-panel: rgba(255, 255, 255, 0.9);
  --ai-surface: rgba(255, 255, 255, 0.96);
  --ai-surface-strong: #ffffff;
  --ai-text: #091624;
  --ai-text-muted: #56677b;
  --ai-border: rgba(16, 42, 71, 0.1);
  --ai-border-strong: rgba(73, 184, 255, 0.24);
  --ai-accent: #0da8bb;
  --ai-accent-strong: #206cf0;
  --ai-accent-warm: #c78a17;
  --ai-shadow: 0 30px 80px rgba(74, 104, 135, 0.12);
  --ai-grid: rgba(32, 108, 240, 0.05);
  --ai-code: #f6f9fc;
  --ai-code-border: rgba(16, 42, 71, 0.08);
}

html,
body {
  background:
    radial-gradient(circle at top right, rgba(245, 184, 59, 0.14), transparent 26%),
    radial-gradient(circle at 70% 18%, rgba(62, 212, 205, 0.18), transparent 30%),
    radial-gradient(circle at 50% -8%, rgba(38, 138, 255, 0.22), transparent 24%),
    var(--ai-bg);
  color: var(--ai-text);
  font-family: var(--ai-font);
}

.book {
  background: transparent;
}

.book .book-body,
.book .book-body .body-inner,
.book .book-body .page-wrapper,
.book .book-body .page-wrapper .page-inner,
.book .book-body .page-wrapper .page-inner section,
.book .book-body .page-wrapper .page-inner section.normal {
  background: transparent !important;
}

.book .book-body,
.book .book-body .body-inner,
.book .book-body .page-wrapper,
.book .book-body .page-wrapper .page-inner {
  color: var(--ai-text);
}

.book-summary {
  width: 320px;
  background:
    linear-gradient(180deg, rgba(6, 15, 23, 0.94), rgba(8, 18, 29, 0.96)),
    var(--ai-bg-elevated);
  border-right: 1px solid var(--ai-border);
  box-shadow: inset -1px 0 0 rgba(255, 255, 255, 0.02);
}

:root[data-theme="light"] .book-summary {
  background:
    linear-gradient(180deg, rgba(247, 251, 255, 0.94), rgba(239, 246, 252, 0.98)),
    var(--ai-bg-elevated);
}

.book-summary ul.summary li.header {
  color: var(--ai-text-muted);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 11px;
  font-weight: 700;
  padding-top: 24px;
}

.book-summary ul.summary li a,
.book-summary ul.summary li span {
  color: var(--ai-text-muted);
  border-radius: 12px;
  margin: 2px 14px;
  padding: 11px 14px;
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.book-summary ul.summary li.active > a,
.book-summary ul.summary li a:hover {
  color: var(--ai-text);
  background: rgba(255, 255, 255, 0.05);
  transform: translateX(2px);
}

.book-summary nav,
.book-summary ul.summary,
.book-summary ul.summary li {
  color: var(--ai-text-muted) !important;
}

#book-search-input {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

#book-search-input input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.book-header.ai-header {
  height: 76px;
  border-bottom: 1px solid var(--ai-border);
  background:
    linear-gradient(180deg, rgba(11, 21, 32, 0.76), rgba(11, 21, 32, 0.58)),
    var(--ai-bg-elevated);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 28px;
}

:root[data-theme="light"] .book-header.ai-header {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(248, 251, 255, 0.84)),
    var(--ai-bg-elevated);
}

.ai-header-brand,
.ai-header-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.ai-logo-link {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  color: var(--ai-text) !important;
  text-decoration: none !important;
  font-weight: 700;
  font-size: 22px;
}

.ai-logo-mark {
  width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  border: 1px solid rgba(104, 227, 233, 0.38);
  background: linear-gradient(135deg, rgba(104, 227, 233, 0.18), rgba(73, 184, 255, 0.08));
  color: var(--ai-accent);
  box-shadow: 0 14px 36px rgba(0, 0, 0, 0.2);
}

.ai-logo-text {
  font-size: 19px;
  letter-spacing: -0.02em;
}

.ai-search-trigger {
  border: 1px solid var(--ai-border-strong);
  background: rgba(255, 255, 255, 0.04);
  color: var(--ai-text);
  border-radius: 14px;
  height: 46px;
  padding: 0 16px;
  min-width: 220px;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
  cursor: pointer;
}

.ai-search-trigger-shortcut {
  margin-left: auto;
  color: var(--ai-text-muted);
  font-size: 12px;
}

.ai-search-palette[hidden] {
  display: none !important;
}

.ai-search-palette {
  position: fixed;
  inset: 0;
  z-index: 60;
}

.ai-search-palette-backdrop {
  position: absolute;
  inset: 0;
  border: 0;
  width: 100%;
  background: rgba(2, 10, 18, 0.7);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  cursor: default;
}

.ai-search-dialog {
  position: relative;
  max-width: 760px;
  margin: 82px auto 0;
  padding: 0 18px;
}

.ai-search-shell {
  border-radius: 26px;
  border: 1px solid var(--ai-border-strong);
  background:
    linear-gradient(180deg, rgba(19, 34, 49, 0.98), rgba(10, 20, 31, 0.98)),
    var(--ai-surface-strong);
  box-shadow: 0 36px 120px rgba(0, 0, 0, 0.42);
  overflow: hidden;
}

:root[data-theme="light"] .ai-search-shell {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.98), rgba(244, 249, 254, 0.98)),
    var(--ai-surface-strong);
  box-shadow: 0 36px 120px rgba(60, 88, 116, 0.18);
}

.ai-search-shell-bar {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px 20px;
  border-bottom: 1px solid var(--ai-border);
}

.ai-search-shell-icon {
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  background: rgba(104, 227, 233, 0.1);
  border: 1px solid rgba(104, 227, 233, 0.14);
  color: var(--ai-accent);
  font-weight: 700;
}

.ai-search-shell-input {
  flex: 1 1 auto;
  min-width: 0;
  border: 0;
  background: transparent;
  color: var(--ai-text);
  font-size: 22px;
  line-height: 1.2;
  font-weight: 600;
  outline: 0;
  box-shadow: none;
}

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

.ai-search-shell-close {
  border: 1px solid var(--ai-border);
  background: rgba(255, 255, 255, 0.04);
  color: var(--ai-text-muted);
  border-radius: 12px;
  min-width: 48px;
  height: 38px;
  padding: 0 12px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
}

.ai-search-shell-close:hover {
  color: var(--ai-text);
  border-color: var(--ai-border-strong);
}

.ai-theme-switcher {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px;
  border-radius: 14px;
  border: 1px solid var(--ai-border);
  background: rgba(255, 255, 255, 0.04);
}

.ai-theme-option {
  border: 0;
  background: transparent;
  color: var(--ai-text-muted);
  border-radius: 10px;
  padding: 9px 14px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}

.ai-theme-option.is-active,
.ai-theme-option:hover {
  background: rgba(104, 227, 233, 0.12);
  color: var(--ai-text);
}

.book .book-body .page-wrapper .page-inner {
  max-width: 1120px;
  padding: 44px 56px 80px;
}

.page-wrapper {
  background:
    linear-gradient(var(--ai-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--ai-grid) 1px, transparent 1px),
    transparent;
  background-size: 36px 36px;
}

.markdown-section {
  color: var(--ai-text);
}

.markdown-section h1 {
  color: var(--ai-text);
  font-size: 64px;
  line-height: 1.02;
  letter-spacing: -0.05em;
  margin-bottom: 18px;
}

.markdown-section h2,
.markdown-section h3,
.markdown-section h4 {
  color: var(--ai-text);
}

.markdown-section p,
.markdown-section li,
.markdown-section blockquote,
.markdown-section table {
  color: var(--ai-text-muted);
}

.markdown-section strong,
.markdown-section a {
  color: var(--ai-text);
}

.markdown-section a {
  text-decoration-thickness: 1px;
}

.markdown-section table {
  display: table;
  width: 100%;
  font-size: 0.94rem;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--ai-border);
  border-radius: 18px;
  overflow: hidden;
}

.markdown-section table th,
.markdown-section table td {
  border-color: var(--ai-border) !important;
}

.markdown-section table th {
  color: var(--ai-text) !important;
  background: rgba(255, 255, 255, 0.04) !important;
}

.markdown-section table td {
  color: var(--ai-text-muted) !important;
}

.markdown-section table tr {
  background: rgba(255, 255, 255, 0.02) !important;
}

.markdown-section table tr:nth-child(2n) {
  background: rgba(255, 255, 255, 0.04) !important;
}

.markdown-section pre {
  border-radius: 18px;
  background: var(--ai-code);
  border: 1px solid var(--ai-code-border);
  box-shadow: var(--ai-shadow);
}

.markdown-section code {
  color: var(--ai-accent);
  background: rgba(104, 227, 233, 0.08);
  border-radius: 8px;
  padding: 0.16em 0.4em;
}

.markdown-section pre code {
  background: transparent;
  padding: 0;
}

.markdown-section blockquote {
  border-left: 4px solid var(--ai-accent);
  background: rgba(73, 184, 255, 0.08);
  padding: 0.9rem 1rem;
  border-radius: 0 14px 14px 0;
}

.page-inner section.normal > h1:first-child {
  margin-top: 0;
}

.navigation {
  color: var(--ai-text) !important;
}

.book .book-body .navigation {
  color: var(--ai-text-muted) !important;
}

.book .book-body .navigation:hover {
  color: var(--ai-text) !important;
}

.ai-home-hero {
  position: relative;
  margin-bottom: 36px;
  padding: 8px 0 10px;
}

.ai-home-lead {
  max-width: 820px;
  font-size: 30px;
  line-height: 1.25;
  color: var(--ai-text-muted);
  margin-bottom: 26px;
}

.ai-home-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 34px;
}

.ai-home-action {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 16px 22px;
  border-radius: 16px;
  text-decoration: none !important;
  border: 1px solid var(--ai-border-strong);
  background: rgba(255, 255, 255, 0.04);
  color: var(--ai-text) !important;
  font-weight: 600;
  box-shadow: var(--ai-shadow);
}

.ai-home-action.is-primary {
  background: linear-gradient(135deg, rgba(20, 174, 185, 0.24), rgba(32, 108, 240, 0.16));
}

.ai-home-action.is-warm {
  border-color: rgba(255, 202, 98, 0.32);
  background: linear-gradient(135deg, rgba(255, 202, 98, 0.14), rgba(199, 138, 23, 0.06));
}

.ai-home-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(300px, 0.85fr);
  gap: 18px;
  margin-bottom: 18px;
}

.ai-panel {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0.02));
  border: 1px solid var(--ai-border);
  border-radius: var(--ai-radius-xl);
  box-shadow: var(--ai-shadow);
  padding: 24px 24px 22px;
}

.ai-panel h2,
.ai-panel h3 {
  margin-top: 0;
}

.ai-link-list {
  display: grid;
  gap: 14px;
}

.ai-link-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: 14px 0;
  border-bottom: 1px solid var(--ai-border);
}

.ai-link-item:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.ai-link-icon {
  flex: 0 0 auto;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--ai-text);
  background: rgba(104, 227, 233, 0.12);
  border: 1px solid rgba(104, 227, 233, 0.16);
}

.ai-link-copy a {
  color: var(--ai-text) !important;
  font-weight: 600;
  text-decoration: none;
}

.ai-command-panel pre {
  margin: 0;
}

.ai-three-up {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 18px;
}

.ai-mini-card {
  border-radius: 22px;
  border: 1px solid var(--ai-border);
  background: rgba(255, 255, 255, 0.03);
  padding: 24px;
  min-height: 180px;
}

.ai-mini-card h3 {
  margin-top: 14px;
  margin-bottom: 10px;
}

.ai-mini-icon {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: rgba(73, 184, 255, 0.12);
  border: 1px solid rgba(73, 184, 255, 0.14);
  color: var(--ai-accent-strong);
}

body.is-home .markdown-section > h1:first-child,
body.is-home .markdown-section > p:first-of-type,
body.is-home .markdown-section > blockquote:first-of-type {
  display: none;
}

@media (max-width: 1200px) {
  .book .book-body .page-wrapper .page-inner {
    padding: 34px 34px 72px;
  }

  .ai-home-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 960px) {
  .book-summary {
    width: 300px;
  }

  .book-header.ai-header {
    padding: 14px 18px;
    height: auto;
    min-height: 76px;
    flex-wrap: wrap;
    gap: 14px;
  }

  .ai-header-actions {
    width: 100%;
    justify-content: space-between;
    flex-wrap: wrap;
  }

  .ai-search-trigger {
    min-width: 0;
    flex: 1 1 280px;
  }

  .markdown-section h1 {
    font-size: 48px;
  }

  .ai-home-lead {
    font-size: 24px;
  }

  .ai-three-up {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 680px) {
  .book .book-body .page-wrapper .page-inner {
    padding: 26px 20px 56px;
  }

  .markdown-section h1 {
    font-size: 40px;
  }

  .ai-logo-text {
    font-size: 17px;
  }

  .ai-home-actions {
    flex-direction: column;
  }

  .ai-home-action {
    width: 100%;
    justify-content: space-between;
  }

  .ai-theme-switcher {
    width: 100%;
    justify-content: space-between;
  }

  .ai-theme-option {
    flex: 1 1 0;
    text-align: center;
  }
}

.ai-home-title {
  font-size: 72px;
  line-height: 0.98;
  letter-spacing: -0.055em;
  color: var(--ai-text);
  margin: 0 0 18px;
  max-width: 900px;
}

.ai-overview-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 8px;
}

.ai-overview-table th,
.ai-overview-table td {
  text-align: left;
  padding: 14px 12px;
  border-bottom: 1px solid var(--ai-border);
  color: var(--ai-text-muted);
  vertical-align: top;
}

.ai-overview-table th {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ai-text);
}

.ai-overview-table td strong {
  color: var(--ai-text);
}

.ai-overview-table tr:last-child td {
  border-bottom: 0;
}

.ai-panel-link {
  display: inline-flex;
  align-items: center;
  margin-top: 18px;
  color: var(--ai-accent) !important;
  text-decoration: none !important;
  font-weight: 600;
}

.ai-command-code {
  display: block;
  padding: 22px 24px;
  border-radius: 18px;
  background: var(--ai-code);
  border: 1px solid var(--ai-code-border);
  color: var(--ai-text);
  overflow-x: auto;
  font-size: 15px;
  line-height: 1.8;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.02);
}

#book-search-results {
  color: var(--ai-text);
  min-height: 180px;
  max-height: min(62vh, 680px);
  overflow: auto;
}

#book-search-results .search-results {
  padding: 0;
}

#book-search-results .search-results .search-results-title {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 20px 12px;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ai-text-muted);
  border-bottom: 1px solid var(--ai-border);
}

#book-search-results .search-results .search-results-title .search-results-count:empty,
#book-search-results .search-results .search-results-title .search-query:empty {
  display: none;
}

#book-search-results .search-results .search-query {
  color: var(--ai-text);
  letter-spacing: normal;
  text-transform: none;
}

#book-search-results .search-results .search-results-panel {
  padding: 10px 12px 14px;
}

#book-search-results .search-results .has-results,
#book-search-results .search-results .no-results {
  display: none;
}

#book-search-results.open .search-results .has-results {
  display: block;
}

#book-search-results.no-results .search-results .has-results {
  display: none;
}

#book-search-results.no-results .search-results .no-results {
  display: block;
}

#book-search-results .search-results .search-results-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

#book-search-results .search-results .has-results .search-results-item,
#book-search-results .search-results .no-results p {
  color: var(--ai-text-muted);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--ai-border);
  border-radius: 18px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.02);
}

#book-search-results .search-results .has-results .search-results-item {
  padding: 14px 16px;
}

#book-search-results .search-results .no-results p {
  margin: 0;
  padding: 18px 16px;
}

#book-search-results .search-results .has-results .search-results-item h3 {
  margin: 0 0 6px;
  font-size: 16px;
}

#book-search-results .search-results .has-results .search-results-item h3 a,
#book-search-results .search-results .has-results .search-results-item a {
  color: var(--ai-text) !important;
  text-decoration: none;
}

#book-search-results .search-results .has-results .search-results-item h3 a:hover,
#book-search-results .search-results .has-results .search-results-item a:hover {
  color: var(--ai-accent) !important;
}

#book-search-results .search-results .has-results .search-results-item p {
  color: var(--ai-text-muted);
  margin: 0;
}

#book-search-results .search-results .has-results .search-results-item a:focus-visible {
  outline: 2px solid var(--ai-accent);
  outline-offset: 4px;
  border-radius: 6px;
}

.ai-search-hintbar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  padding: 12px 20px 18px;
  border-top: 1px solid var(--ai-border);
  color: var(--ai-text-muted);
  font-size: 12px;
}

.ai-search-hintbar span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.ai-search-hintbar kbd {
  border: 1px solid var(--ai-border);
  border-bottom-width: 2px;
  border-radius: 8px;
  min-width: 26px;
  padding: 4px 7px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--ai-text);
  font: inherit;
  font-weight: 700;
  text-align: center;
}

.font-settings .dropdown-menu {
  background: var(--ai-surface-strong);
  border: 1px solid var(--ai-border);
  border-radius: 18px;
  box-shadow: var(--ai-shadow);
}

.font-settings .dropdown-menu .dropdown-caret .caret-inner {
  border-bottom-color: var(--ai-surface-strong) !important;
}

.font-settings .dropdown-menu .buttons,
.font-settings .dropdown-menu .font-family-list {
  border-color: var(--ai-border) !important;
}

.font-settings .dropdown-menu .button,
.font-settings .dropdown-menu li {
  color: var(--ai-text-muted);
}

.font-settings .dropdown-menu .button:hover,
.font-settings .dropdown-menu li:hover,
.font-settings .dropdown-menu .button.active,
.font-settings .dropdown-menu li.active {
  color: var(--ai-text);
  background: rgba(255, 255, 255, 0.05);
}

.glossary-term {
  color: var(--ai-accent) !important;
  text-decoration-color: rgba(104, 227, 233, 0.35);
}

@media (max-width: 960px) {
  .ai-home-title {
    font-size: 56px;
  }
}

@media (max-width: 680px) {
  .ai-home-title {
    font-size: 42px;
  }

  .ai-search-dialog {
    margin-top: 16px;
    padding: 0 10px;
  }

  .ai-search-shell-bar {
    gap: 10px;
    padding: 14px;
  }

  .ai-search-shell-input {
    font-size: 18px;
  }

  .ai-search-shell-close {
    min-width: 44px;
    height: 34px;
    padding: 0 10px;
  }

  #book-search-results {
    max-height: calc(100vh - 220px);
  }
}