:root {
      --ink: #06131f; --paper: #ffffff; --line: #dbe3ea; --muted: #4b5563; --signal: #0b63ce; --page: #f8f7f2;
      --font-sans: HelveticaNeue, "Helvetica Neue", Helvetica, Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", "Yu Gothic", YuGothic, Meiryo, sans-serif;
      --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;
      font-family: var(--font-sans); color: var(--ink); background: var(--paper);
    }
    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body { margin: 0; font-size: 16px; line-height: 1.8; font-feature-settings: "palt"; -webkit-font-smoothing: antialiased; word-wrap: break-word; background: var(--page); }
    a { color: inherit; }
    .site-header { display: flex; align-items: center; justify-content: space-between; gap: 18px; min-height: 62px; padding: 14px clamp(20px, 4vw, 58px) 10px; background: var(--page); }
    main { padding-bottom: clamp(60px, 9vw, 120px); }
    .wrap { max-width: 880px; margin: 0 auto; padding: 0 clamp(20px, 4vw, 40px); }
    .breadcrumb { padding-top: clamp(28px, 5vw, 56px); color: var(--muted); font-family: var(--font-mono); font-size: 11px; font-weight: 780; letter-spacing: 0.06em; }
    .breadcrumb a { text-decoration: underline; text-underline-offset: 3px; }
    .section-label { margin: 0 0 8px; color: var(--signal); font-family: var(--font-mono); font-size: 11px; font-weight: 780; letter-spacing: 0.12em; text-transform: uppercase; }
    .guide-head { margin-top: 18px; }
    .guide-head h1 { margin: 0 0 14px; font-size: clamp(28px, 4.4vw, 44px); line-height: 1.2; font-weight: 840; }
    .guide-lead { margin: 0 0 12px; font-size: clamp(15.5px, 1.7vw, 17px); line-height: 1.9; }
    .guide-note { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }
    .guide-tabs { display: flex; flex-wrap: wrap; gap: 8px; margin: 24px 0 0; padding: 0; list-style: none; }
    .guide-tabs a { display: inline-flex; align-items: center; min-height: 40px; padding: 6px 16px; border: 1px solid var(--line); border-radius: 999px; background: var(--paper); font-size: 14px; font-weight: 760; text-decoration: none; }
    .guide-tabs a:hover, .guide-tabs a:focus-visible { border-color: var(--signal); color: var(--signal); outline: none; }
    .guide-tabs a[aria-current="page"] { background: var(--ink); border-color: var(--ink); color: var(--paper); }
    .chapter-block { margin-top: clamp(40px, 6vw, 60px); scroll-margin-top: 80px; }
    .chapter-block > h2 { margin: 0 0 14px; padding-bottom: 8px; border-bottom: 2px solid var(--ink); font-size: clamp(19px, 2.4vw, 24px); line-height: 1.4; font-weight: 820; }
    .chapter-block > h2 small { margin-left: 8px; color: var(--muted); font-family: var(--font-mono); font-size: 12px; font-weight: 700; }
    .ch-sub { margin-left: 10px; font-size: 0.72em; font-weight: 760; }
    .loc { color: var(--muted); font-family: var(--font-mono); font-size: 12px; font-weight: 700; letter-spacing: 0.02em; }
    .back-to-book { margin-top: clamp(48px, 6vw, 72px); padding: 22px; border: 1px solid var(--line); border-radius: 16px; background: var(--paper); }
    .back-to-book h2 { margin: 0 0 8px; font-size: 18px; }
    .back-to-book p { margin: 0 0 14px; color: var(--muted); font-size: 14.5px; }
    .back-to-book .links { display: flex; flex-wrap: wrap; gap: 10px; }
    .btn { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: 10px 18px; border: 1px solid var(--ink); font-size: 14px; font-weight: 780; text-decoration: none; }
    .btn-primary { background: var(--ink); color: var(--paper); }
    .btn-secondary { background: var(--paper); color: var(--ink); }
    .btn-primary:hover, .btn-primary:focus-visible { background: var(--signal); border-color: var(--signal); outline: none; }
    .btn-secondary:hover, .btn-secondary:focus-visible { border-color: var(--signal); color: var(--signal); outline: none; }
    .credits { margin-top: 28px; padding-top: 16px; border-top: 1px solid var(--line); }
    .credits p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.8; }

    .chapter-art { display: block; width: 100%; height: auto; aspect-ratio: 3 / 1; object-fit: cover; margin: 0 0 18px; border-radius: 14px; background: #000; }
    .guide-fig { margin: clamp(28px, 4vw, 40px) 0 0; padding: clamp(18px, 3vw, 28px); border: 1px solid var(--line); border-radius: 16px; background: var(--paper); }
    .chapter-block .guide-fig { margin: 0 0 18px; }
    .fig-label { display: inline-block; margin: 0 0 4px; color: var(--signal); font-family: var(--font-mono); font-size: 11px; font-weight: 780; letter-spacing: 0.12em; }
    .fig-title { margin: 0 0 16px; font-size: 18px; line-height: 1.45; font-weight: 820; }
    .guide-fig figcaption { margin-top: 14px; color: var(--muted); font-size: 13px; line-height: 1.75; }
    .guide-fig figcaption a { color: var(--signal); }
    /* 4つの爆発 */
    .boom { display: grid; gap: 10px; }
    .boom-name { display: block; font-size: 16px; font-weight: 820; line-height: 1.4; }
    .boom-desc { display: block; margin-top: 2px; color: var(--muted); font-size: 13px; line-height: 1.65; }
    .boom-economy { padding: 16px; border: 2px solid var(--ink); border-radius: 14px; }
    .boom-inner { display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr); gap: 10px; align-items: stretch; margin-top: 14px; }
    .boom-box { padding: 12px 14px; border: 1px solid var(--line); border-radius: 12px; background: #f8fafc; }
    .boom-mutual { display: grid; place-content: center; text-align: center; color: var(--signal); font-size: 24px; font-weight: 800; line-height: 1; }
    .boom-mutual small { display: block; margin-top: 4px; font-size: 11px; font-weight: 760; }
    .boom-arrow { text-align: center; color: var(--signal); font-size: 14px; font-weight: 800; }
    .boom-source { border: 0; background: var(--ink); color: var(--paper); }
    .boom-source .boom-desc { color: var(--paper); opacity: 0.8; }
    /* マトリクス */
    .matrix { display: grid; grid-template-columns: auto minmax(0, 1fr); grid-template-rows: auto auto; gap: 6px 10px; }
    .matrix-y { grid-row: 1; grid-column: 1; writing-mode: vertical-rl; align-self: center; color: var(--muted); font-size: 12px; font-weight: 760; line-height: 1.5; }
    .matrix-grid { grid-row: 1; grid-column: 2; display: grid; grid-template-columns: auto minmax(0, 1fr) minmax(0, 1fr); gap: 6px; }
    .matrix-x { grid-row: 2; grid-column: 2; text-align: center; color: var(--muted); font-size: 12px; font-weight: 760; }
    .mx-row { display: grid; align-content: center; padding-right: 4px; font-size: 13px; font-weight: 780; line-height: 1.45; }
    .mx-row small { color: var(--muted); font-size: 11px; font-weight: 700; }
    .mx-col { text-align: center; font-size: 13px; font-weight: 780; }
    .mx-cell { display: grid; place-content: center; min-height: 76px; padding: 10px; border: 1px solid var(--line); border-radius: 10px; background: #f8fafc; text-align: center; font-size: 13px; line-height: 1.6; }
    .mx-on { border-color: var(--ink); background: var(--ink); color: var(--paper); }
    /* 2層 */
    .layers { display: grid; gap: 8px; max-width: 560px; margin: 0 auto; }
    .layer { display: grid; grid-template-columns: auto minmax(0, 1fr); column-gap: 12px; padding: 14px 16px; border: 1px solid var(--ink); border-radius: 12px; }
    .layer-no { grid-row: span 2; align-self: center; padding: 3px 8px; border-radius: 6px; background: var(--ink); color: var(--paper); font-family: var(--font-mono); font-size: 11px; font-weight: 800; }
    .layer b { font-size: 16px; }
    .layer span:last-child { color: var(--muted); font-size: 13px; line-height: 1.65; }
    .layer-gap { text-align: center; color: var(--muted); font-size: 12.5px; font-weight: 760; }
    .layer-goal { justify-self: center; margin-top: 4px; padding: 6px 18px; border: 1.5px solid var(--signal); border-radius: 999px; color: var(--signal); font-size: 13.5px; font-weight: 800; }
    /* はしご */
    .ladder { display: grid; grid-template-columns: auto minmax(0, 1fr) minmax(0, 0.8fr); gap: 14px; align-items: stretch; }
    .ladder-axis { display: flex; flex-direction: column; justify-content: space-between; padding: 4px 0; border-right: 2px solid var(--signal); padding-right: 8px; color: var(--signal); font-size: 11.5px; font-weight: 800; writing-mode: horizontal-tb; }
    .ladder-rungs { display: grid; gap: 8px; margin: 0; padding: 0 14px; list-style: none; border-left: 3px solid var(--ink); border-right: 3px solid var(--ink); }
    .rung { display: grid; place-content: center; min-height: 34px; border-top: 3px solid var(--ink); color: var(--ink); font-size: 12.5px; font-weight: 760; text-align: center; line-height: 1.4; }
    .rung-top { color: var(--signal); }
    .ladder-note { display: grid; align-content: start; gap: 2px; padding-top: 4px; font-size: 13px; line-height: 1.6; }
    .ladder-note span { color: var(--muted); }
    /* 棒グラフ */
    .fig-legend { display: flex; flex-wrap: wrap; gap: 6px 16px; margin: 0 0 12px; padding: 0; list-style: none; font-size: 13px; }
    .sw { display: inline-block; width: 12px; height: 12px; margin-right: 6px; border-radius: 3px; vertical-align: -1px; }
    .bars { display: grid; gap: 8px; margin: 0; padding: 0; list-style: none; }
    .bars li { display: grid; grid-template-columns: 4.2em minmax(0, 1fr) 3.4em; gap: 10px; align-items: center; font-size: 13.5px; }
    .bar-label { font-weight: 780; text-underline-offset: 3px; }
    .bar-label:hover, .bar-label:focus-visible { color: var(--signal); outline: none; }
    .bar { display: flex; width: var(--w); height: 18px; border-radius: 4px; overflow: hidden; }
    .bar-n { color: var(--muted); font-family: var(--font-mono); font-size: 12px; font-weight: 700; }
    .seg[data-kind="term"], .sw[data-kind="term"] { background: var(--ink); }
    .seg[data-kind="misreading"], .sw[data-kind="misreading"] { background: var(--ink); }
    .seg[data-kind="clarification"], .sw[data-kind="clarification"] { background: var(--signal); }
    .seg[data-kind="open_objection"], .sw[data-kind="open_objection"] { background: #c77a2b; }
    @media (max-width: 560px) {
      .boom-inner { grid-template-columns: 1fr; }
      .boom-mutual { font-size: 20px; }
      .boom-mutual { transform: rotate(90deg); }
      .boom-mutual small { transform: rotate(-90deg); }
      .mx-cell { min-height: 64px; padding: 8px 6px; font-size: 12px; }
      .ladder { grid-template-columns: auto minmax(0, 1fr); }
      .ladder-note { grid-column: 1 / -1; grid-template-columns: auto 1fr; gap: 8px; }
    }
    html[data-color-mode="dark"] .boom-box:not(.boom-source), html[data-color-mode="dark"] .mx-cell:not(.mx-on) { background: #16213a; }
    html[data-color-mode="dark"] .boom-source, html[data-color-mode="dark"] .mx-on, html[data-color-mode="dark"] .layer-no { color: #0b1220; }
    html[data-color-mode="dark"] .boom-source .boom-desc { color: #0b1220; }

    /* 冒頭：挿絵を背景に敷く */
    .guide-hero { position: relative; isolation: isolate; overflow: hidden; margin-top: 18px; padding: clamp(28px, 5vw, 52px) clamp(20px, 4vw, 40px); border-radius: 18px; background: #000; color: #f3f6fb; }
    .guide-hero .hero-bg { position: absolute; inset: 0; z-index: -1; width: 100%; height: 100%; object-fit: cover; object-position: 70% 50%; opacity: 0.85; }
    .guide-hero::before { content: ""; position: absolute; inset: 0; z-index: -1; background: linear-gradient(90deg, rgba(0,0,0,0.92) 0%, rgba(0,0,0,0.78) 45%, rgba(0,0,0,0.15) 100%); }
    .guide-hero .section-label { color: #7fc4ff; }
    .guide-hero h1 { max-width: 16em; color: #fff; }
    .guide-hero .guide-lead { max-width: 36em; color: rgba(243,246,251,0.92); }
    .guide-hero .guide-note { max-width: 36em; color: rgba(243,246,251,0.72); }
    /* 章へ移動：挿絵のタイル */
    .chapter-nav { display: grid; grid-template-columns: repeat(auto-fill, minmax(118px, 1fr)); gap: 8px; margin: 22px 0 0; padding: 0; list-style: none; }
    .chapter-nav a { position: relative; display: block; overflow: hidden; aspect-ratio: 2.2 / 1; border-radius: 10px; background: #000; color: #fff; text-decoration: none; }
    .chapter-nav img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: 0.7; transition: opacity .2s, transform .3s; }
    .chapter-nav span { position: absolute; left: 10px; bottom: 7px; font-size: 13.5px; font-weight: 800; text-shadow: 0 1px 6px rgba(0,0,0,0.9); }
    .chapter-nav a:hover img, .chapter-nav a:focus-visible img { opacity: 1; transform: scale(1.06); }
    .chapter-nav a:focus-visible { outline: 2px solid var(--signal); outline-offset: 2px; }
    /* 章見出しの帯 */
    .ch-band { position: relative; isolation: isolate; overflow: hidden; margin: 0 0 16px; border-radius: 14px; background: #000; }
    .ch-band .chapter-art { position: absolute; inset: 0; z-index: -1; width: 100%; height: 100%; margin: 0; border-radius: 0; object-fit: cover; object-position: 75% 50%; opacity: 0.9; aspect-ratio: auto; }
    .ch-band::before { content: ""; position: absolute; inset: 0; z-index: -1; background: linear-gradient(90deg, rgba(0,0,0,0.9) 0%, rgba(0,0,0,0.6) 50%, rgba(0,0,0,0.05) 100%); }
    .chapter-block .ch-band > h2 { margin: 0; padding: clamp(26px, 4vw, 40px) clamp(16px, 3vw, 26px); border: 0; color: #fff; }
    .ch-band h2 small, .ch-band .ch-sub { color: rgba(255,255,255,0.78); }
    .ch-band .ch-sub { display: block; margin: 4px 0 0; font-size: 0.68em; }
    .ch-band h2 small { display: inline-block; margin: 6px 0 0; }
    /* 透過の光を図や締めに重ねる */
    .guide-fig { position: relative; isolation: isolate; overflow: hidden; }
    .fig-glow { position: absolute; z-index: -1; right: -18%; top: -30%; width: 75%; height: auto; opacity: 0.22; pointer-events: none; }
    .back-to-book { position: relative; isolation: isolate; overflow: hidden; display: grid; grid-template-columns: 96px minmax(0, 1fr); column-gap: 20px; align-items: start; }
    .back-to-book > * { grid-column: 2; }
    .back-to-book .back-cover { grid-column: 1; grid-row: 1 / span 3; width: 96px; height: auto; box-shadow: 0 10px 24px rgba(6,19,31,0.25); }
    .back-glow { position: absolute; z-index: -1; right: -10%; bottom: -40%; width: 70%; height: auto; opacity: 0.3; pointer-events: none; grid-column: auto !important; }
    @media (max-width: 460px) { .back-to-book { grid-template-columns: 72px minmax(0, 1fr); column-gap: 14px; } .back-to-book .back-cover { width: 72px; } }
    .photo-credits { margin-top: 18px; color: var(--muted); font-size: 12.5px; }
    .photo-credits summary { cursor: pointer; font-weight: 760; }
    .photo-credits ul { margin: 8px 0 0; padding-left: 1.2em; }
    .photo-credits a { color: var(--signal); }
    html[data-color-mode="dark"] body, html[data-color-mode="dark"] .site-header { background: #0b1220; color: #e8eef5; }
    html[data-color-mode="dark"] { --ink: #e8eef5; --paper: #111a2b; --line: #263247; --muted: #a8b3c2; --signal: #6aa8ff; --page: #0b1220; }
    html[data-color-mode="dark"] .btn-primary, html[data-color-mode="dark"] .guide-tabs a[aria-current="page"] { color: #0b1220; }

    .term-search { margin: 26px 0 0; }
    .term-search label { display: block; margin-bottom: 6px; font-size: 13.5px; font-weight: 760; }
    .term-search input { width: 100%; min-height: 46px; padding: 10px 14px; border: 1px solid var(--line); border-radius: 10px; background: var(--paper); color: var(--ink); font: inherit; font-size: 16px; }
    .term-search input:focus-visible { outline: 2px solid var(--signal); outline-offset: 1px; border-color: var(--signal); }
    .term-count { margin: 8px 0 0; color: var(--muted); font-size: 13px; }
    .terms { display: grid; gap: 12px; margin: 0; padding: 0; list-style: none; }
    .term { padding: 18px 20px; border: 1px solid var(--line); border-radius: 14px; background: var(--paper); scroll-margin-top: 80px; }
    .term:target { border-color: var(--signal); box-shadow: 0 0 0 2px rgba(11, 99, 206, 0.18); }
    .term h3 { margin: 0 0 8px; font-size: 18px; line-height: 1.45; font-weight: 820; }
    .term h3 a { text-decoration: none; }
    .term h3 a:hover, .term h3 a:focus-visible { color: var(--signal); outline: none; }
    .uses { margin: 0; padding: 0; list-style: none; }
    .uses li { padding: 8px 0 0; }
    .uses li + li { margin-top: 8px; border-top: 1px dashed var(--line); }
    .uses p { margin: 2px 0 0; font-size: 15px; line-height: 1.85; }
    .term-links { display: flex; flex-wrap: wrap; gap: 8px 14px; margin: 10px 0 0; padding: 0; list-style: none; font-size: 13.5px; }
    .term-links a { color: var(--signal); font-weight: 760; text-underline-offset: 3px; }

    .term-person { display: flex; align-items: center; gap: 8px; margin: -2px 0 8px; color: var(--muted); font-size: 12.5px; }
    .term-person img { width: 32px; height: 32px; border-radius: 50%; object-fit: cover; object-position: 50% 25%; }
    .term-person b { color: var(--ink); }
    .no-hit { padding: 20px; color: var(--muted); }