:root {
    --tokisync-bg: #1b2028;
    --tokisync-surface: #222832;
    --tokisync-surface-2: #29313d;
    --tokisync-surface-3: #303947;
    --tokisync-border: #3a4554;
    --tokisync-border-soft: #313a47;
    --tokisync-text: #e7ebf2;
    --tokisync-text-muted: #b2bac8;
    --tokisync-text-faint: #8792a3;
    --tokisync-accent: #59b9e9;
    --tokisync-accent-soft: rgba(89, 185, 233, 0.13);
    --tokisync-accent-ink: #08222e;
    --tokisync-warning: #f2b84b;
    --tokisync-warning-soft: rgba(242, 184, 75, 0.12);
    --tokisync-danger: #ef6a6a;
    --tokisync-danger-soft: rgba(239, 106, 106, 0.12);
    --tokisync-success: #8fd97a;
    --tokisync-success-soft: rgba(143, 217, 122, 0.12);
    --tokisync-shadow: 0 10px 26px rgba(0,0,0,0.22);
    --tokisync-radius-s: 6px;
    --tokisync-radius-m: 10px;
    --tokisync-font-sans: "Noto Sans JP", "Yu Gothic UI", "Hiragino Kaku Gothic ProN", "Hiragino Sans", "Meiryo", system-ui, sans-serif;
    --tokisync-font-mono: ui-monospace, "SF Mono", "JetBrains Mono", Consolas, "Courier New", monospace;
  }

  @media (prefers-color-scheme: light) {
    :root {
      --tokisync-bg: #eef0f3;
      --tokisync-surface: #ffffff;
      --tokisync-surface-2: #f4f5f7;
      --tokisync-surface-3: #eceef2;
      --tokisync-border: #dbdfe6;
      --tokisync-border-soft: #e6e9ee;
      --tokisync-text: #454c5c;
      --tokisync-text-muted: #707786;
      --tokisync-text-faint: #8b93a1;
      --tokisync-accent: #0284c7;
      --tokisync-accent-soft: rgba(2, 132, 199, 0.09);
      --tokisync-accent-ink: #ffffff;
      --tokisync-warning: #b45f06;
      --tokisync-warning-soft: rgba(180, 95, 6, 0.10);
      --tokisync-danger: #d63b3b;
      --tokisync-danger-soft: rgba(214, 59, 59, 0.09);
      --tokisync-success: #3f9142;
      --tokisync-success-soft: rgba(63, 145, 66, 0.10);
      --tokisync-shadow: 0 12px 28px rgba(40, 48, 66, 0.14);
    }
  }

  :root[data-theme="dark"] {
    --tokisync-bg: #1b2028; --tokisync-surface: #222832; --tokisync-surface-2: #29313d; --tokisync-surface-3: #303947;
    --tokisync-border: #3a4554; --tokisync-border-soft: #313a47; --tokisync-text: #e7ebf2; --tokisync-text-muted: #b2bac8; --tokisync-text-faint: #8792a3;
    --tokisync-accent: #59b9e9; --tokisync-accent-soft: rgba(89,185,233,0.13); --tokisync-accent-ink: #08222e;
    --tokisync-warning: #f2b84b; --tokisync-warning-soft: rgba(242,184,75,0.12);
    --tokisync-danger: #ef6a6a; --tokisync-danger-soft: rgba(239,106,106,0.12);
    --tokisync-success: #8fd97a; --tokisync-success-soft: rgba(143,217,122,0.12);
    --tokisync-shadow: 0 10px 26px rgba(0,0,0,0.22);
  }
  :root[data-theme="light"] {
    --tokisync-bg: #eef0f3; --tokisync-surface: #ffffff; --tokisync-surface-2: #f4f5f7; --tokisync-surface-3: #eceef2;
    --tokisync-border: #dbdfe6; --tokisync-border-soft: #e6e9ee; --tokisync-text: #454c5c; --tokisync-text-muted: #707786; --tokisync-text-faint: #8b93a1;
    --tokisync-accent: #0284c7; --tokisync-accent-soft: rgba(2,132,199,0.09); --tokisync-accent-ink: #ffffff;
    --tokisync-warning: #b45f06; --tokisync-warning-soft: rgba(180,95,6,0.10);
    --tokisync-danger: #d63b3b; --tokisync-danger-soft: rgba(214,59,59,0.09);
    --tokisync-success: #3f9142; --tokisync-success-soft: rgba(63,145,66,0.10);
    --tokisync-shadow: 0 12px 28px rgba(40,48,66,0.14);
  }

  * { box-sizing: border-box; }
  html { scroll-behavior: smooth; }
  @media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
  }

  body {
    margin: 0;
    background: var(--tokisync-bg);
    color: var(--tokisync-text);
    font-family: var(--tokisync-font-sans);
    font-size: 16px;
    line-height: 1.8;
    -webkit-font-smoothing: antialiased;
  }

  /* ---------- progress bar ---------- */
  #progress {
    position: fixed;
    top: 0; left: 0;
    height: 3px;
    width: 0%;
    background: var(--tokisync-accent);
    z-index: 60;
    transition: width 80ms linear;
  }

  /* ---------- layout ---------- */
  .layout {
    display: flex;
    align-items: flex-start;
    max-width: 1180px;
    margin: 0 auto;
  }

  .sidebar {
    position: sticky;
    top: 0;
    height: 100vh;
    width: 280px;
    flex: none;
    overflow-y: auto;
    padding: 28px 18px 40px;
    border-right: 1px solid var(--tokisync-border);
    background: var(--tokisync-surface);
  }

  .brand {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 4px 10px 20px;
  }
  .brand-logo {
    display: flex;
    align-items: center;
    padding: 1px 6px;
  }
  .brand-name {
    font-weight: 700;
    font-size: 16px;
    letter-spacing: 0.01em;
    line-height: 1;
  }
  .brand-sub {
    display: block;
    font-size: 12px;
    color: var(--tokisync-text-faint);
    padding: 0 10px 18px;
  }

  .nav-group {
    margin-bottom: 4px;
  }
  .nav-group-label {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.09em;
    color: var(--tokisync-text-faint);
    text-transform: uppercase;
    padding: 14px 10px 6px;
  }
  .nav-link {
    display: flex;
    align-items: baseline;
    gap: 10px;
    padding: 7px 10px;
    border-radius: var(--tokisync-radius-s);
    color: var(--tokisync-text-muted);
    text-decoration: none;
    font-size: 14px;
    line-height: 1.4;
  }
  .nav-link:hover {
    color: var(--tokisync-text);
    background: var(--tokisync-surface-2);
  }
  .nav-link .num {
    font-family: var(--tokisync-font-mono);
    font-size: 11px;
    color: var(--tokisync-text-faint);
    flex: none;
    width: 1.4em;
  }
  .nav-link.active {
    color: var(--tokisync-accent);
    background: var(--tokisync-accent-soft);
    font-weight: 700;
  }
  .nav-link.active .num { color: var(--tokisync-accent); }
  .nav-link-primary {
    color: var(--tokisync-text);
    font-weight: 700;
  }

  .theme-toggle {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 18px 10px 0;
    padding: 8px 10px;
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-s);
    background: var(--tokisync-surface-2);
    color: var(--tokisync-text-muted);
    font-size: 12.5px;
    cursor: pointer;
    width: calc(100% - 20px);
  }
  .theme-toggle:hover { color: var(--tokisync-text); border-color: var(--tokisync-text-faint); }
  .theme-toggle svg { flex: none; }

  .nav-toggle {
    display: none;
  }

  /* ---------- main content ---------- */
  .content {
    flex: 1;
    min-width: 0;
    padding: 56px 56px 120px;
  }

  /* ---------- breadcrumb ---------- */
  .breadcrumb {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 24px;
    font-size: 13px;
    color: var(--tokisync-text-muted);
  }
  .breadcrumb-link {
    color: var(--tokisync-text-muted);
    text-decoration: none;
  }
  .breadcrumb-link:hover {
    color: var(--tokisync-accent);
  }
  .breadcrumb-sep {
    color: var(--tokisync-text-faint);
  }
  .breadcrumb-current {
    color: var(--tokisync-text);
    font-weight: 600;
  }
  .breadcrumb-dropdown {
    position: relative;
    display: inline-flex;
  }
  .breadcrumb-dropdown summary {
    list-style: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 4px;
  }
  .breadcrumb-dropdown summary::-webkit-details-marker {
    display: none;
  }
  .breadcrumb-dropdown summary::after {
    content: "▾";
    font-size: 10px;
    color: var(--tokisync-text-faint);
  }
  .breadcrumb-menu {
    position: absolute;
    top: calc(100% + 8px);
    left: 0;
    margin: 0;
    padding: 6px;
    list-style: none;
    min-width: 160px;
    background: var(--tokisync-surface);
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    box-shadow: var(--tokisync-shadow);
    z-index: 20;
  }
  .breadcrumb-menu li + li {
    margin-top: 2px;
  }
  .breadcrumb-menu a {
    display: block;
    padding: 8px 10px;
    border-radius: var(--tokisync-radius-s);
    color: var(--tokisync-text);
    text-decoration: none;
    font-size: 13px;
  }
  .breadcrumb-menu a:hover {
    background: var(--tokisync-accent-soft);
  }
  .breadcrumb-menu a[aria-current="page"] {
    color: var(--tokisync-accent);
    font-weight: 600;
  }

  .doc-header {
    margin-bottom: 56px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--tokisync-border);
  }
  .doc-eyebrow {
    font-family: var(--tokisync-font-mono);
    font-size: 12.5px;
    letter-spacing: 0.1em;
    color: var(--tokisync-accent);
    text-transform: uppercase;
    margin: 0 0 14px;
  }
  .doc-title {
    margin-bottom: 10px;
  }

  .doc-title img {
    width: 90%;
  }
  .doc-store-link {
    display: flex;
    width: fit-content;
    align-items: center;
    gap: 6px;
    margin: 0 0 18px auto;
    padding: 8px 14px;
    border-radius: var(--tokisync-radius-s);
    border: 1px solid var(--tokisync-accent);
    color: var(--tokisync-accent);
    text-decoration: none;
    font-size: 13.5px;
    font-weight: 700;
    line-height: 1.8;
    transition: background 150ms ease, color 150ms ease;
  }
  .doc-store-link:hover {
    background: var(--tokisync-accent-soft);
  }
  .doc-store-link.is-disabled {
    border-color: var(--tokisync-border);
    color: var(--tokisync-text-faint);
    font-weight: 600;
    cursor: default;
  }

  .doc-header-actions {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 10px;
    margin: 0 0 18px;
  }
  .doc-header-actions .doc-store-link {
    margin: 0;
  }

  /* ---------- share widget ---------- */
  .share-widget {
    position: relative;
  }
  .share-btn {
    appearance: none;
    -webkit-appearance: none;
    display: flex;
    align-items: center;
    gap: 6px;
    margin: 0;
    padding: 8px 14px;
    border-radius: var(--tokisync-radius-s);
    border: 1px solid var(--tokisync-accent);
    background: none;
    color: var(--tokisync-accent);
    font-family: var(--tokisync-font-sans);
    font-size: 13.5px;
    font-weight: 700;
    line-height: 1.8;
    cursor: pointer;
    transition: background 150ms ease, color 150ms ease;
  }
  .share-btn:hover,
  .share-btn[aria-expanded="true"] {
    background: var(--tokisync-accent-soft);
  }
  .share-btn svg { display: block; }

  .share-menu[hidden] {
    display: none;
  }
  .share-menu {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    z-index: 10;
    display: flex;
    flex-direction: column;
    min-width: 170px;
    padding: 6px;
    border-radius: var(--tokisync-radius-m);
    border: 1px solid var(--tokisync-border);
    background: var(--tokisync-surface);
    box-shadow: var(--tokisync-shadow);
  }
  .share-menu-item {
    display: block;
    width: 100%;
    padding: 9px 10px;
    border: none;
    border-radius: var(--tokisync-radius-s);
    background: none;
    color: var(--tokisync-text);
    font-family: var(--tokisync-font-sans);
    font-size: 13px;
    text-align: left;
    text-decoration: none;
    cursor: pointer;
  }
  .share-menu-item:hover {
    background: var(--tokisync-accent-soft);
    color: var(--tokisync-accent);
  }

  .doc-lede {
    font-size: 16.5px;
    color: var(--tokisync-text-muted);
    margin: 0;
  }

  /* ---------- guide home / quick start ---------- */
  .guide-home,
  .quick-start {
    max-width: 760px;
    scroll-margin-top: 24px;
  }
  .guide-home {
    margin: 0 0 72px;
  }
  .guide-home-heading {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    gap: 24px;
    margin-bottom: 22px;
  }
  .section-eyebrow {
    margin: 0 0 6px;
    color: var(--tokisync-accent);
    font-family: var(--tokisync-font-mono);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.1em;
  }
  .guide-home h2 {
    margin: 0 0 6px;
    font-size: 27px;
    line-height: 1.4;
  }
  .guide-home-heading p:last-child,
  .quick-start-lede {
    margin: 0;
    color: var(--tokisync-text-muted);
  }
  .start-button,
  .secondary-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 44px;
    padding: 9px 16px;
    border-radius: var(--tokisync-radius-s);
    font-size: 14px;
    font-weight: 700;
    line-height: 1.4;
    text-decoration: none;
  }
  .start-button {
    flex: none;
    background: var(--tokisync-accent);
    color: var(--tokisync-accent-ink);
  }
  .start-button:hover { filter: brightness(1.06); }
  .secondary-button {
    border: 1px solid var(--tokisync-border);
    color: var(--tokisync-text);
    background: var(--tokisync-surface);
  }
  .secondary-button:hover { border-color: var(--tokisync-accent); color: var(--tokisync-accent); }
  .purpose-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
  }
  .purpose-card {
    display: grid;
    grid-template-columns: 38px 1fr;
    grid-template-rows: auto auto;
    column-gap: 12px;
    padding: 16px;
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    background: var(--tokisync-surface);
    color: var(--tokisync-text);
    text-decoration: none;
    transition: border-color 140ms ease, background 140ms ease, transform 140ms ease;
  }
  .purpose-card:hover {
    border-color: var(--tokisync-accent);
    background: var(--tokisync-accent-soft);
    transform: translateY(-1px);
  }
  .purpose-icon {
    grid-row: 1 / 3;
    display: grid;
    place-items: center;
    width: 38px;
    height: 38px;
    border-radius: var(--tokisync-radius-s);
    background: var(--tokisync-accent-soft);
    color: var(--tokisync-accent);
    font-size: 19px;
  }
  .purpose-card strong { font-size: 15px; }
  .purpose-card > span:last-child {
    color: var(--tokisync-text-muted);
    font-size: 13px;
    line-height: 1.55;
  }
  .support-links {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 18px;
    margin-top: 18px;
    padding-top: 16px;
    border-top: 1px solid var(--tokisync-border-soft);
  }
  .support-links a { font-size: 13.5px; text-decoration: none; }
  .support-links a::after { content: " →"; }

  .quick-start {
    margin: 0 0 88px;
    padding: 24px;
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    background: var(--tokisync-surface);
  }
  .step-list {
    display: grid;
    gap: 0;
    margin: 24px 0;
    padding: 0;
    list-style: none;
  }
  .step-list li {
    position: relative;
    display: grid;
    grid-template-columns: 34px 1fr;
    gap: 12px;
    margin: 0;
    padding: 0 0 22px;
  }
  .step-list li:last-child { padding-bottom: 0; }
  .step-list li:not(:last-child)::before {
    content: "";
    position: absolute;
    top: 32px;
    bottom: 0;
    left: 16px;
    width: 1px;
    background: var(--tokisync-border);
  }
  .step-number {
    position: relative;
    z-index: 1;
    display: grid;
    place-items: center;
    width: 34px;
    height: 34px;
    border-radius: 50%;
    background: var(--tokisync-accent);
    color: var(--tokisync-accent-ink);
    font-family: var(--tokisync-font-mono);
    font-size: 13px;
    font-weight: 800;
  }
  .step-list strong { display: block; margin: 3px 0 4px; }
  .step-list p { margin: 0; color: var(--tokisync-text-muted); font-size: 14px; }
  .quick-start-actions { display: flex; flex-wrap: wrap; gap: 10px; }
  .obs-paths {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    margin-top: 24px;
    padding-top: 20px;
    border-top: 1px solid var(--tokisync-border);
  }
  .obs-paths.compact { margin: 18px 0; padding: 0; border: 0; }
  .obs-paths > div,
  .obs-paths > a {
    padding: 14px 16px;
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    background: var(--tokisync-surface-2);
  }
  .obs-path-link {
    display: block;
    color: var(--tokisync-text);
    text-decoration: none;
    transition: border-color 140ms ease, background 140ms ease;
  }
  .obs-path-link:hover {
    border-color: var(--tokisync-accent);
    background: var(--tokisync-accent-soft);
  }
  .path-label {
    display: block;
    margin-bottom: 4px;
    color: var(--tokisync-accent);
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.04em;
  }
  .obs-paths strong { display: block; margin-bottom: 4px; font-size: 14px; }
  .obs-paths p { margin: 0; color: var(--tokisync-text-muted); font-size: 13px; line-height: 1.65; }
  .path-jump {
    display: block;
    margin-top: 8px;
    color: var(--tokisync-accent);
    font-size: 12px;
    font-weight: 700;
  }

  section.chapter {
    max-width: 700px;
    margin: 0 0 88px;
    scroll-margin-top: 24px;
  }
  section.chapter:last-of-type { margin-bottom: 24px; }

  .chapter-kicker {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 10px;
  }
  .chapter-kicker .num {
    font-family: var(--tokisync-font-mono);
    font-size: 13px;
    font-weight: 700;
    color: var(--tokisync-accent-ink);
    background: var(--tokisync-accent);
    border-radius: 5px;
    padding: 3px 8px;
  }
  .chapter-kicker .label {
    font-size: 12.5px;
    color: var(--tokisync-text-faint);
    letter-spacing: 0.04em;
  }

  h2.chapter-title {
    position: relative;
    font-size: 27px;
    font-weight: 800;
    margin: 0 0 24px;
    padding-bottom: 10px;
    letter-spacing: -0.005em;
    text-wrap: balance;
  }
  h2.chapter-title::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 52px;
    height: 3px;
    border-radius: 999px;
    background: var(--tokisync-accent);
  }

  section.chapter > p:first-of-type {
    font-size: 16.5px;
    color: var(--tokisync-text-muted);
  }

  h3 {
    font-size: 18px;
    font-weight: 700;
    margin: 34px 0 12px;
    padding-top: 4px;
  }
  section.chapter > h3 {
    display: flex;
    align-items: center;
    gap: 9px;
    padding: 0 0 8px;
    border-bottom: 1px solid var(--tokisync-border);
  }
  section.chapter > h3::before {
    content: "";
    flex: none;
    width: 5px;
    height: 1.15em;
    border-radius: 999px;
    background: var(--tokisync-accent);
  }
  h4 {
    font-size: 15px;
    font-weight: 700;
    margin: 24px 0 8px;
    color: var(--tokisync-text);
  }
  .guide-subtitle {
    scroll-margin-top: 24px;
    padding: 10px 12px;
    border-left: 3px solid var(--tokisync-accent);
    border-bottom: 1px solid var(--tokisync-border-soft);
    background: linear-gradient(90deg, var(--tokisync-accent-soft), transparent 72%);
  }

  .keyword-mark {
    color: var(--tokisync-text);
    font-weight: 700;
    text-decoration-line: underline;
    text-decoration-color: var(--tokisync-accent);
    text-decoration-thickness: 2px;
    text-underline-offset: 4px;
  }

  p { margin: 0 0 14px; }
  section.chapter p { color: var(--tokisync-text); }

  ul, ol {
    margin: 0 0 16px;
    padding-left: 1.3em;
  }
  li { margin-bottom: 8px; }
  li:last-child { margin-bottom: 0; }
  li > ul, li > ol { margin-top: 8px; }

  /* 長い説明リストは、カード化せず余白と細い区切りで読み分ける */
  section.chapter > ul {
    display: grid;
    gap: 14px;
    padding: 0;
    list-style: none;
  }
  section.chapter > ul > li {
    position: relative;
    margin: 0;
    padding: 0 0 14px 22px;
    border-bottom: 1px solid var(--tokisync-border-soft);
  }
  section.chapter > ul > li::before {
    content: "";
    position: absolute;
    top: 0.72em;
    left: 3px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--tokisync-accent);
  }
  section.chapter > ul > li:last-child { padding-bottom: 0; border-bottom: 0; }
  section.chapter > ul > li strong:first-child { color: var(--tokisync-accent); }

  /* 「項目名: 説明」の一覧は、設定項目としてカードで区切る */
  section.chapter > ul > li:has(> strong:first-child) {
    padding: 13px 15px;
    border: 1px solid var(--tokisync-border-soft);
    border-radius: var(--tokisync-radius-s);
    background: var(--tokisync-surface-2);
  }
  section.chapter > ul > li:has(> strong:first-child)::before { display: none; }
  section.chapter > ul > li:has(> strong:first-child) > strong:first-child {
    display: inline-block;
    margin-right: 0.2em;
  }

  /* 操作手順は番号を軸に縦へ読み進める */
  section.chapter > ol {
    display: grid;
    gap: 22px;
    padding: 0;
    list-style: none;
    counter-reset: chapter-step;
  }
  section.chapter > ol > li {
    position: relative;
    min-height: 34px;
    margin: 0;
    padding: 3px 0 0 48px;
    counter-increment: chapter-step;
  }
  section.chapter > ol > li:not(:last-child)::after {
    content: "";
    position: absolute;
    top: 34px;
    bottom: -22px;
    left: 16px;
    width: 1px;
    background: var(--tokisync-border);
  }
  section.chapter > ol > li::before {
    content: counter(chapter-step);
    position: absolute;
    top: 0;
    left: 0;
    display: grid;
    place-items: center;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--tokisync-accent);
    color: var(--tokisync-accent-ink);
    font-family: var(--tokisync-font-mono);
    font-size: 12px;
    font-weight: 800;
  }

  .feature-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
    margin: 0 0 16px;
  }
  .feature-grid a {
    display: block;
    padding: 14px;
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    background: var(--tokisync-surface-2);
    color: var(--tokisync-text);
    text-decoration: none;
  }
  .feature-grid a:hover { border-color: var(--tokisync-accent); }
  .feature-grid a:last-child:nth-child(odd) { grid-column: 1 / -1; }
  .feature-grid strong {
    display: block;
    margin-bottom: 3px;
    color: var(--tokisync-accent);
  }
  .feature-grid span {
    display: block;
    color: var(--tokisync-text-muted);
    font-size: 13px;
    line-height: 1.55;
  }
  .section-note {
    padding: 10px 12px;
    border-radius: var(--tokisync-radius-s);
    background: var(--tokisync-accent-soft);
    font-size: 14px;
  }

  strong { font-weight: 700; color: var(--tokisync-text); }
  a { color: var(--tokisync-accent); }

  code {
    font-family: var(--tokisync-font-mono);
    font-size: 0.88em;
    background: var(--tokisync-surface-2);
    border: 1px solid var(--tokisync-border-soft);
    border-radius: 4px;
    padding: 0.1em 0.4em;
  }

  pre.url-block {
    font-family: var(--tokisync-font-mono);
    font-size: 14.5px;
    background: var(--tokisync-surface-2);
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    padding: 14px 18px;
    overflow-x: auto;
    color: var(--tokisync-accent);
    margin: 0 0 16px;
  }

  .callout {
    display: flex;
    gap: 12px;
    border: 1px solid var(--tokisync-border);
    border-left: 3px solid var(--tokisync-accent);
    background: var(--tokisync-surface-2);
    border-radius: var(--tokisync-radius-m);
    padding: 14px 18px;
    margin: 0 0 18px;
    font-size: 14.5px;
  }
  .callout p { margin: 0; color: var(--tokisync-text); }
  .callout .icon { flex: none; margin-top: 2px; }
  .callout.warn { border-left-color: var(--tokisync-warning); background: var(--tokisync-warning-soft); }
  .callout.warn .icon { color: var(--tokisync-warning); }
  .callout.danger { border-left-color: var(--tokisync-danger); background: var(--tokisync-danger-soft); }
  .callout.danger .icon { color: var(--tokisync-danger); }
  .callout.note .icon { color: var(--tokisync-accent); }

  figure.screenshot {
    margin: 0 0 20px;
  }
  figure.screenshot img {
    display: block;
    width: 100%;
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    box-shadow: var(--tokisync-shadow);
    background: var(--tokisync-surface-2);
  }
  figure.screenshot figcaption {
    margin-top: 8px;
    font-size: 13px;
    color: var(--tokisync-text-faint);
  }
  .screenshot-row {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    margin: 0 0 20px;
  }
  .screenshot-row figure.screenshot {
    flex: 1 1 240px;
    min-width: 0;
    margin: 0;
  }

  .dock-guide {
    display: grid;
    gap: 18px;
    margin: 18px 0 24px;
  }
  .dock-guide figure.screenshot {
    position: relative;
    margin: 0;
    padding: 14px;
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    background: var(--tokisync-surface-2);
  }
  .dock-guide .shot-frame {
    position: relative;
  }
  .dock-guide figure.screenshot img {
    border: 0;
    box-shadow: none;
  }
  .dock-guide .shot-number {
    position: absolute;
    z-index: 2;
    top: 4px;
    left: 4px;
    display: grid;
    place-items: center;
    width: 32px;
    height: 32px;
    border: 2px solid #fff;
    border-radius: 50%;
    background: var(--tokisync-accent);
    color: var(--tokisync-accent-ink);
    font-family: var(--tokisync-font-mono);
    font-size: 13px;
    font-weight: 800;
    box-shadow: 0 2px 8px rgba(0,0,0,0.28);
  }
  .dock-guide .shot-highlight {
    position: absolute;
    z-index: 1;
    border: 3px solid var(--tokisync-accent);
    border-radius: 4px;
    background: color-mix(in srgb, var(--tokisync-accent) 12%, transparent);
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--tokisync-accent) 20%, transparent);
    pointer-events: none;
  }
  .dock-guide figure.screenshot figcaption {
    margin: 10px 2px 0;
    color: var(--tokisync-text-muted);
    line-height: 1.65;
  }
  .dock-guide figure.screenshot figcaption strong {
    display: block;
    color: var(--tokisync-text);
    font-size: 14px;
  }

  .kbd-row {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin: 0 0 18px;
  }
  .kbd {
    font-family: var(--tokisync-font-mono);
    font-size: 13px;
    font-weight: 600;
    color: var(--tokisync-text);
    background: var(--tokisync-surface-2);
    border: 1px solid var(--tokisync-border);
    border-bottom-width: 2px;
    border-radius: var(--tokisync-radius-s);
    padding: 5px 10px;
  }

  .grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin: 0 0 18px;
  }
  @media (max-width: 640px) {
    .grid-2 { grid-template-columns: 1fr; }
    .guide-home-heading { display: block; }
    .guide-home-heading .start-button { margin-top: 16px; }
    .purpose-grid,
    .obs-paths,
    .feature-grid { grid-template-columns: 1fr; }
    .feature-grid a:last-child:nth-child(odd) { grid-column: auto; }
    .quick-start { padding: 20px 16px; }
  }
  .fact-card {
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    padding: 16px 18px;
    background: var(--tokisync-surface);
  }
  .fact-card .fact-title {
    font-family: var(--tokisync-font-mono);
    font-size: 12px;
    letter-spacing: 0.04em;
    color: var(--tokisync-accent);
    margin-bottom: 6px;
  }
  .fact-card p { color: var(--tokisync-text-muted); font-size: 14px; margin: 0; }
  .fact-card strong { display: block; font-size: 15px; margin-bottom: 4px; }

  table {
    width: 100%;
    border-collapse: collapse;
    margin: 0 0 18px;
    font-size: 14.5px;
  }
  thead th {
    text-align: left;
    font-size: 12px;
    letter-spacing: 0.04em;
    color: var(--tokisync-text-faint);
    border-bottom: 1px solid var(--tokisync-border);
    padding: 0 10px 8px 0;
    font-weight: 600;
  }
  tbody td {
    padding: 10px 10px 10px 0;
    border-bottom: 1px solid var(--tokisync-border-soft);
    vertical-align: top;
  }
  tbody tr:last-child td { border-bottom: none; }

  .chapter-nav {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    margin-top: 44px;
    padding-top: 24px;
    border-top: 1px solid var(--tokisync-border);
  }
  .chapter-nav a {
    flex: 1;
    text-decoration: none;
    color: var(--tokisync-text-muted);
    border: 1px solid var(--tokisync-border);
    border-radius: var(--tokisync-radius-m);
    padding: 12px 16px;
    font-size: 13.5px;
    display: block;
    transition: border-color 120ms ease, color 120ms ease;
  }
  .chapter-nav a:hover { border-color: var(--tokisync-accent); color: var(--tokisync-accent); }
  .chapter-nav a.next { text-align: right; }
  .chapter-nav a .dir { display: block; font-size: 11px; color: var(--tokisync-text-faint); margin-bottom: 3px; letter-spacing: 0.04em; }

  .toc-end {
    max-width: 700px;
    padding: 28px 0 0;
    color: var(--tokisync-text-faint);
    font-size: 13px;
    border-top: 1px solid var(--tokisync-border);
  }

  /* ---------- mobile ---------- */
  @media (max-width: 900px) {
    .layout { display: block; }
    .sidebar {
      position: fixed;
      inset: 0 30% 0 0;
      z-index: 50;
      width: auto;
      transform: translateX(-105%);
      transition: transform 180ms ease;
      box-shadow: var(--tokisync-shadow);
    }
    .sidebar.open { transform: translateX(0); }
    .sidebar-scrim {
      display: none;
      position: fixed; inset: 0;
      background: rgba(0,0,0,0.4);
      z-index: 45;
    }
    .sidebar-scrim.open { display: block; }
    .nav-toggle {
      display: flex;
      align-items: center;
      gap: 8px;
      position: fixed;
      top: 14px;
      left: 14px;
      z-index: 55;
      background: var(--tokisync-surface);
      color: var(--tokisync-text);
      border: 1px solid var(--tokisync-border);
      border-radius: var(--tokisync-radius-s);
      padding: 9px 12px;
      font-size: 13px;
      font-family: var(--tokisync-font-sans);
      box-shadow: var(--tokisync-shadow);
      cursor: pointer;
    }
    .nav-toggle.is-open { display: none; }
    .content { padding: 90px 22px 100px; }
    .doc-title { font-size: 26px; }
  }