@layer reset, tokens, base, layout, components, article, responsive;

@layer reset {
  *, *::before, *::after { box-sizing: border-box; }
  html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
  body, h1, h2, h3, h4, p, ul, ol, figure { margin: 0; }
  button, input { font: inherit; }
  button { color: inherit; }
  img { display: block; max-width: 100%; }
  a { color: inherit; }
  [hidden] { display: none !important; }
}

@layer tokens {
  :root {
    color-scheme: light;
    --ink-950: oklch(18% 0.009 85);
    --ink-900: oklch(23% 0.009 85);
    --ink-700: oklch(39% 0.012 85);
    --ink-500: oklch(56% 0.012 85);
    --paper-50: oklch(97% 0.012 88);
    --paper-100: oklch(94% 0.014 88);
    --paper-200: oklch(89% 0.016 88);
    --signal-500: oklch(72% 0.16 67);
    --signal-600: oklch(63% 0.16 62);
    --danger: oklch(58% 0.17 29);
    --success: oklch(57% 0.11 150);

    --bg: var(--paper-50);
    --surface: oklch(99% 0.006 88);
    --surface-raised: oklch(100% 0.004 88);
    --text: var(--ink-950);
    --text-soft: var(--ink-700);
    --text-muted: var(--ink-500);
    --line: var(--paper-200);
    --line-strong: oklch(72% 0.015 88);
    --accent: var(--signal-600);
    --accent-ink: oklch(22% 0.025 65);
    --accent-soft: oklch(91% 0.06 75);
    --rail: oklch(16% 0.008 85);
    --rail-raised: oklch(20% 0.009 85);
    --rail-text: oklch(94% 0.01 88);
    --rail-muted: oklch(67% 0.01 88);
    --overlay: oklch(14% 0.01 85 / .68);
    --note-bg: oklch(94% 0.024 80);
    --hint-bg: oklch(94% 0.025 151);

    --font-display: "DIN Alternate", "Avenir Next Condensed", "Helvetica Neue", sans-serif;
    --font-ui: "Avenir Next", "Noto Sans SC", "PingFang SC", "Helvetica Neue", sans-serif;
    --font-reading: "Avenir Next", "Noto Sans SC", "PingFang SC", "Helvetica Neue", sans-serif;
    --text-size: 1rem;

    --space-1: .25rem;
    --space-2: .5rem;
    --space-3: .75rem;
    --space-4: 1rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-24: 6rem;

    --radius-sm: .35rem;
    --radius-md: .7rem;
    --ease-out: cubic-bezier(.16, 1, .3, 1);
    --ease-state: cubic-bezier(.65, 0, .35, 1);
    --shadow-dialog: 0 1.5rem 5rem oklch(12% 0.01 85 / .24);
  }

  :root[data-theme="dark"] {
    color-scheme: dark;
    --bg: oklch(16% 0.008 85);
    --surface: oklch(19% 0.009 85);
    --surface-raised: oklch(23% 0.01 85);
    --text: oklch(92% 0.012 88);
    --text-soft: oklch(76% 0.012 88);
    --text-muted: oklch(63% 0.012 88);
    --line: oklch(29% 0.011 85);
    --line-strong: oklch(40% 0.012 85);
    --accent: var(--signal-500);
    --accent-ink: oklch(20% 0.025 65);
    --accent-soft: oklch(28% 0.055 70);
    --note-bg: oklch(24% 0.022 72);
    --hint-bg: oklch(24% 0.024 151);
    --overlay: oklch(8% 0.008 85 / .78);
  }
}

@layer base {
  body {
    min-width: 20rem;
    min-height: 100dvh;
    overflow-x: hidden;
    background: var(--bg);
    color: var(--text);
    font-family: var(--font-ui);
    font-size: 1rem;
    line-height: 1.5;
    font-kerning: normal;
  }

  body:has(dialog[open]) { overflow: hidden; }

  button, a { -webkit-tap-highlight-color: transparent; }
  button { border: 0; background: none; cursor: pointer; }
  button:focus { outline: none; }
  :where(button, a, input, summary):focus-visible {
    outline: .16rem solid var(--accent);
    outline-offset: .18rem;
  }

  .skip-link {
    position: fixed;
    z-index: 1000;
    top: .5rem;
    left: .5rem;
    padding: .75rem 1rem;
    transform: translateY(-140%);
    background: var(--accent);
    color: var(--accent-ink);
    font-weight: 700;
    text-decoration: none;
  }
  .skip-link:focus { transform: translateY(0); }

  svg {
    width: 1.35rem;
    height: 1.35rem;
    fill: none;
    stroke: currentColor;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 1.8;
  }

  ::selection { background: var(--accent); color: var(--accent-ink); }
}

@layer layout {
  .reading-progress {
    position: fixed;
    z-index: 90;
    inset: 0 0 auto;
    height: .18rem;
    pointer-events: none;
  }
  .reading-progress span {
    display: block;
    width: 0;
    height: 100%;
    transform-origin: left;
    background: var(--accent);
    transition: width 100ms linear;
  }

  .mobile-header {
    position: sticky;
    z-index: 40;
    top: 0;
    display: grid;
    grid-template-columns: 3rem 1fr 3rem;
    align-items: center;
    min-height: calc(3.5rem + env(safe-area-inset-top));
    padding: env(safe-area-inset-top) max(.5rem, env(safe-area-inset-right)) 0 max(.5rem, env(safe-area-inset-left));
    border-bottom: 1px solid var(--line);
    background: var(--bg);
  }

  .mobile-context {
    overflow: hidden;
    color: var(--text-soft);
    font-family: var(--font-display);
    font-size: .75rem;
    font-weight: 700;
    letter-spacing: .14em;
    text-align: center;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .icon-button {
    display: grid;
    width: 3rem;
    height: 3rem;
    place-items: center;
  }
  .icon-button .mark {
    color: var(--accent);
    font-family: var(--font-display);
    font-size: .82rem;
    font-weight: 800;
    letter-spacing: -.02em;
  }

  .desktop-rail { display: none; }
  #main-content { min-width: 0; }

  .bottom-nav {
    position: fixed;
    z-index: 50;
    inset: auto 0 0;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    min-height: calc(4rem + env(safe-area-inset-bottom));
    padding: .25rem max(.25rem, env(safe-area-inset-right)) env(safe-area-inset-bottom) max(.25rem, env(safe-area-inset-left));
    border-top: 1px solid var(--line);
    background: var(--surface);
  }
  .bottom-nav button {
    display: flex;
    min-width: 0;
    min-height: 3.5rem;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: .12rem;
    color: var(--text-muted);
    font-size: .68rem;
    font-weight: 600;
  }
  .bottom-nav svg { width: 1.25rem; height: 1.25rem; }
  .bottom-nav button.active { color: var(--accent); }

  .home-view, .reader-view { padding-bottom: calc(5.5rem + env(safe-area-inset-bottom)); }
}

@layer components {
  .hero {
    position: relative;
    display: flex;
    min-height: min(44rem, calc(100svh - 3.5rem));
    flex-direction: column;
    justify-content: space-between;
    gap: var(--space-12);
    overflow: hidden;
    padding: clamp(1.5rem, 6vw, 3rem) max(1.25rem, env(safe-area-inset-left));
    border-bottom: 1px solid var(--line-strong);
    background-image:
      linear-gradient(to right, var(--line) 1px, transparent 1px),
      linear-gradient(to bottom, var(--line) 1px, transparent 1px);
    background-size: 3rem 3rem;
  }
  .hero::before {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    background: linear-gradient(105deg, var(--bg) 12%, color-mix(in oklch, var(--bg) 84%, transparent) 58%, transparent);
  }
  .hero > * { position: relative; }
  .hero::after {
    content: "05";
    position: absolute;
    top: 15%;
    right: -1.2rem;
    color: color-mix(in oklch, var(--text) 6%, transparent);
    font-family: var(--font-display);
    font-size: clamp(12rem, 55vw, 26rem);
    font-weight: 800;
    line-height: .7;
    letter-spacing: -.12em;
    pointer-events: none;
  }
  .hero-kicker {
    display: flex;
    justify-content: space-between;
    gap: var(--space-4);
    color: var(--text-soft);
    font-family: var(--font-display);
    font-size: .65rem;
    font-weight: 700;
    letter-spacing: .12em;
  }
  .hero-copy { max-width: 44rem; }
  .eyebrow {
    margin-bottom: var(--space-2);
    color: var(--accent);
    font-family: var(--font-display);
    font-size: .78rem;
    font-weight: 700;
    letter-spacing: .18em;
  }
  .hero h1 {
    display: flex;
    flex-direction: column;
    font-family: var(--font-display);
    font-size: clamp(4.25rem, 20vw, 8.5rem);
    font-stretch: condensed;
    font-weight: 800;
    line-height: .73;
    letter-spacing: -.065em;
  }
  .hero h1 span:last-child { color: var(--accent); }
  .hero-intro {
    max-width: 31rem;
    margin-top: var(--space-8);
    color: var(--text-soft);
    font-size: clamp(1rem, 3vw, 1.25rem);
    line-height: 1.65;
  }
  .hero-search {
    display: grid;
    width: 100%;
    max-width: 40rem;
    min-height: 5.5rem;
    grid-template-columns: 2rem 1fr 2rem;
    align-items: center;
    gap: var(--space-3);
    padding: 1rem 1.1rem;
    background: var(--text);
    color: var(--bg);
    text-align: left;
    transition: transform 120ms var(--ease-out), background 120ms var(--ease-state);
  }
  .hero-search:active { transform: scale(.985); }
  .hero-search svg { color: var(--accent); }
  .hero-search span { display: flex; min-width: 0; flex-direction: column; }
  .hero-search strong { font-size: 1rem; }
  .hero-search small { overflow: hidden; margin-top: .2rem; color: color-mix(in oklch, var(--bg) 68%, var(--text)); font-size: .72rem; text-overflow: ellipsis; white-space: nowrap; }
  .hero-search .search-arrow { align-items: flex-end; font-size: 1.25rem; }
  .hero-meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4) var(--space-6);
    padding-top: var(--space-4);
    border-top: 1px solid var(--line-strong);
    color: var(--text-muted);
    font-size: .72rem;
  }
  .hero-meta b { color: var(--text); font-variant-numeric: tabular-nums; }

  .home-content { padding: var(--space-16) max(1.25rem, env(safe-area-inset-left)); }
  .home-content > section + section { margin-top: var(--space-16); }
  .section-heading { display: grid; gap: var(--space-1); margin-bottom: var(--space-6); }
  .section-heading p { color: var(--accent); font-family: var(--font-display); font-size: .65rem; font-weight: 700; letter-spacing: .16em; }
  .section-heading h2 { font-family: var(--font-display); font-size: clamp(1.8rem, 7vw, 2.6rem); line-height: 1; letter-spacing: -.025em; }

  .quick-list, .ruled-list { border-top: 1px solid var(--line-strong); }
  .quick-item, .ruled-item {
    display: grid;
    width: 100%;
    min-height: 4.75rem;
    grid-template-columns: 2.25rem 1fr 1.5rem;
    align-items: center;
    gap: var(--space-3);
    padding: .8rem 0;
    border-bottom: 1px solid var(--line);
    text-align: left;
  }
  .quick-item .num { color: var(--accent); font-family: var(--font-display); font-size: .68rem; font-variant-numeric: tabular-nums; }
  .quick-item strong, .ruled-item strong { display: block; font-size: .98rem; line-height: 1.3; }
  .quick-item small, .ruled-item small { display: block; margin-top: .2rem; color: var(--text-muted); font-size: .72rem; line-height: 1.35; }
  .quick-item .arrow, .ruled-item .arrow { color: var(--text-muted); font-size: 1.1rem; text-align: right; transition: transform 180ms var(--ease-out); }
  .ruled-item { grid-template-columns: 1fr 1.5rem; }

  .section-index { border-top: 1px solid var(--line-strong); }
  .section-row {
    display: grid;
    width: 100%;
    min-height: 4.6rem;
    grid-template-columns: 2.25rem 1fr auto;
    align-items: center;
    gap: var(--space-3);
    padding: .7rem 0;
    border-bottom: 1px solid var(--line);
    text-align: left;
  }
  .section-row .section-number { color: var(--text-muted); font-family: var(--font-display); font-size: .68rem; }
  .section-row strong { font-size: .94rem; }
  .section-row small { color: var(--text-muted); font-size: .7rem; }
  .home-footer { display: grid; gap: var(--space-2); margin-top: var(--space-24); padding-top: var(--space-6); border-top: 1px solid var(--line); color: var(--text-muted); font-size: .66rem; }

  .reader-toolbar {
    display: flex;
    min-height: 3.75rem;
    align-items: center;
    justify-content: space-between;
    padding: 0 max(1rem, env(safe-area-inset-left));
    border-bottom: 1px solid var(--line);
  }
  .back-button { display: flex; min-height: 2.75rem; align-items: center; gap: .25rem; color: var(--text-soft); font-size: .85rem; }
  .back-button svg { width: 1.1rem; }
  .reader-actions { display: flex; gap: .25rem; }
  .reader-actions button { display: grid; width: 2.75rem; height: 2.75rem; place-items: center; color: var(--text-soft); }
  .reader-actions button.active { color: var(--accent); }
  .reader-actions button.active svg { fill: currentColor; }
  .reader-shell { width: min(100%, 52rem); margin-inline: auto; padding: clamp(1.5rem, 6vw, 4rem) max(1.25rem, env(safe-area-inset-left)) var(--space-16); }
  .reader-breadcrumb { margin-bottom: var(--space-6); color: var(--accent); font-family: var(--font-display); font-size: .64rem; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; }
  .article-loading { display: grid; min-height: 50vh; place-content: center; justify-items: center; gap: var(--space-4); color: var(--text-muted); }
  .article-loading span { width: 1.5rem; height: 1.5rem; border: .12rem solid var(--line-strong); border-top-color: var(--accent); border-radius: 50%; animation: spin .8s linear infinite; }
  @keyframes spin { to { transform: rotate(360deg); } }

  .article-pager { display: grid; grid-template-columns: 1fr 1fr; margin-top: var(--space-16); border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong); }
  .article-pager button { display: flex; min-height: 6.5rem; flex-direction: column; justify-content: center; gap: .35rem; padding: 1rem 0; text-align: left; }
  .article-pager button + button { padding-left: 1rem; border-left: 1px solid var(--line); text-align: right; }
  .article-pager button[disabled] { opacity: .35; cursor: default; }
  .article-pager small { color: var(--accent); font-family: var(--font-display); font-size: .58rem; font-weight: 700; letter-spacing: .12em; }
  .article-pager span { display: -webkit-box; overflow: hidden; font-size: .76rem; font-weight: 600; line-height: 1.35; -webkit-box-orient: vertical; -webkit-line-clamp: 3; }

  dialog {
    width: 100%;
    max-width: none;
    height: 100dvh;
    max-height: none;
    margin: 0;
    padding: calc(1rem + env(safe-area-inset-top)) max(1.25rem, env(safe-area-inset-right)) calc(1rem + env(safe-area-inset-bottom)) max(1.25rem, env(safe-area-inset-left));
    overflow: auto;
    border: 0;
    background: var(--surface);
    color: var(--text);
  }
  dialog::backdrop { background: var(--overlay); }
  dialog[open] { animation: dialog-in 280ms var(--ease-out); }
  @keyframes dialog-in { from { opacity: 0; transform: translateY(1rem); } }
  .dialog-header { display: flex; align-items: flex-start; justify-content: space-between; gap: var(--space-4); padding-bottom: var(--space-6); }
  .dialog-header p { color: var(--accent); font-family: var(--font-display); font-size: .62rem; font-weight: 700; letter-spacing: .15em; }
  .dialog-header h2 { margin-top: var(--space-1); font-family: var(--font-display); font-size: 2.2rem; line-height: 1; }
  .dialog-close, .image-close { display: grid; width: 3rem; height: 3rem; place-items: center; color: var(--text-soft); font-size: 1.8rem; font-weight: 300; }

  .search-field {
    display: grid;
    grid-template-columns: 1.5rem 1fr auto;
    align-items: center;
    gap: var(--space-3);
    min-height: 4rem;
    padding: 0 1rem;
    border: 1px solid var(--line-strong);
    background: var(--bg);
  }
  .search-field:focus-within { border-color: var(--accent); box-shadow: 0 0 0 .08rem var(--accent); }
  .search-field input { width: 100%; min-width: 0; padding: 1rem 0; border: 0; outline: 0; background: transparent; color: var(--text); font-size: 1rem; }
  .search-field input::placeholder { color: var(--text-muted); opacity: 1; }
  .search-clear { color: var(--text-muted); font-family: var(--font-display); font-size: .58rem; letter-spacing: .1em; }
  .search-suggestions { display: flex; flex-wrap: wrap; gap: var(--space-2); padding: var(--space-4) 0; }
  .search-suggestions button { min-height: 2.75rem; padding: 0 .85rem; border: 1px solid var(--line); border-radius: 99rem; color: var(--text-soft); font-size: .75rem; }
  .search-status { padding: var(--space-4) 0 var(--space-2); border-bottom: 1px solid var(--line-strong); color: var(--text-muted); font-size: .72rem; }
  .search-result { display: grid; width: 100%; grid-template-columns: 2rem 1fr 1rem; gap: var(--space-3); padding: 1rem 0; border-bottom: 1px solid var(--line); text-align: left; }
  .search-result .result-number { padding-top: .12rem; color: var(--accent); font-family: var(--font-display); font-size: .62rem; font-variant-numeric: tabular-nums; }
  .search-result strong { display: block; font-size: .95rem; line-height: 1.35; }
  .search-result small { display: block; margin-top: .25rem; color: var(--text-muted); font-size: .68rem; }
  .search-result p { display: -webkit-box; overflow: hidden; margin-top: .55rem; color: var(--text-soft); font-size: .75rem; line-height: 1.55; -webkit-box-orient: vertical; -webkit-line-clamp: 2; }
  mark { padding: 0 .08em; background: var(--accent-soft); color: var(--text); }
  .empty-state { display: grid; min-height: 14rem; place-content: center; justify-items: center; gap: var(--space-2); color: var(--text-muted); text-align: center; }
  .empty-state strong { color: var(--text); font-size: 1rem; }
  .empty-state p { max-width: 23rem; font-size: .8rem; }

  .toc-content details, .rail-sections details { border-bottom: 1px solid var(--line); }
  .toc-content summary, .rail-sections summary { display: grid; min-height: 3.5rem; grid-template-columns: 1fr auto; align-items: center; gap: 1rem; list-style: none; cursor: pointer; }
  .toc-content summary::-webkit-details-marker, .rail-sections summary::-webkit-details-marker { display: none; }
  .toc-content summary::after, .rail-sections summary::after { content: "+"; color: var(--text-muted); font-size: 1.1rem; }
  .toc-content details[open] summary::after, .rail-sections details[open] summary::after { content: "−"; }
  .toc-content summary strong { font-size: .9rem; }
  .toc-content summary small { margin-left: .45rem; color: var(--text-muted); font-size: .65rem; }
  .toc-items { padding-bottom: var(--space-3); }
  .toc-items button { display: block; width: 100%; min-height: 3rem; padding: .65rem .75rem; color: var(--text-soft); font-size: .8rem; line-height: 1.4; text-align: left; }
  .toc-items button.active { background: var(--accent-soft); color: var(--text); font-weight: 700; }

  .favorites-content { border-top: 1px solid var(--line-strong); }
  .favorite-row { display: grid; width: 100%; min-height: 4.5rem; grid-template-columns: 1fr auto; align-items: center; gap: var(--space-3); border-bottom: 1px solid var(--line); text-align: left; }
  .favorite-row strong { display: block; font-size: .9rem; }
  .favorite-row small { display: block; margin-top: .2rem; color: var(--text-muted); font-size: .68rem; }
  .favorite-row .remove-favorite { display: grid; width: 3rem; height: 3rem; place-items: center; color: var(--text-muted); font-size: 1.1rem; }

  .image-dialog { display: none; background: oklch(10% 0.006 85); }
  .image-dialog[open] { display: grid; place-items: center; }
  .image-dialog img { max-width: 100%; max-height: calc(100dvh - 4rem); object-fit: contain; }
  .image-close { position: fixed; z-index: 1; top: max(.5rem, env(safe-area-inset-top)); right: max(.5rem, env(safe-area-inset-right)); background: oklch(20% 0.008 85); color: oklch(94% 0.01 88); }

  .toast {
    position: fixed;
    z-index: 100;
    right: 1rem;
    bottom: calc(5rem + env(safe-area-inset-bottom));
    left: 1rem;
    padding: .85rem 1rem;
    transform: translateY(1rem);
    background: var(--text);
    color: var(--bg);
    font-size: .8rem;
    font-weight: 600;
    opacity: 0;
    pointer-events: none;
    transition: transform 220ms var(--ease-out), opacity 180ms var(--ease-state);
  }
  .toast.show { transform: translateY(0); opacity: 1; }
}

@layer article {
  .manual-article { --article-leading: 1.75; font-family: var(--font-reading); font-size: var(--text-size); line-height: var(--article-leading); }
  .manual-article > h1 {
    margin-bottom: var(--space-12);
    font-family: var(--font-display);
    font-size: clamp(2.35rem, 10vw, 4.6rem);
    font-weight: 700;
    line-height: .98;
    letter-spacing: -.045em;
  }
  .manual-article #id_content > * + * { margin-top: var(--space-8); }
  .manual-article .article + .article { margin-top: var(--space-12); padding-top: var(--space-12); border-top: 1px solid var(--line); }
  .manual-article h3 { margin: var(--space-12) 0 var(--space-4); font-family: var(--font-display); font-size: clamp(1.45rem, 5vw, 2rem); line-height: 1.15; letter-spacing: -.02em; }
  .manual-article h4 { margin: var(--space-8) 0 var(--space-3); font-size: 1rem; line-height: 1.35; }
  .manual-article p + p { margin-top: var(--space-4); }
  .manual-article :where(ul, ol) { display: grid; gap: var(--space-3); margin: var(--space-4) 0; padding-left: 1.35rem; }
  .manual-article ol > li::marker { color: var(--accent); font-family: var(--font-display); font-weight: 800; }
  .manual-article li > p + p { margin-top: var(--space-2); }
  .manual-article a { color: var(--accent); text-decoration-color: color-mix(in oklch, var(--accent) 45%, transparent); text-underline-offset: .18em; }
  .manual-article img { width: auto; max-height: 76vh; margin: var(--space-8) auto; cursor: zoom-in; }
  .manual-article .table-scroll { margin: var(--space-8) calc(max(1.25rem, env(safe-area-inset-left)) * -1); overflow-x: auto; padding: 0 max(1.25rem, env(safe-area-inset-left)); -webkit-overflow-scrolling: touch; }
  .manual-article table { width: 100%; min-width: 35rem; border-collapse: collapse; font-size: .82em; line-height: 1.5; }
  .manual-article :where(th, td) { padding: .7rem .75rem; border: 1px solid var(--line); vertical-align: top; text-align: left; }
  .manual-article th { background: var(--surface-raised); font-weight: 700; }
  .manual-article .note, .manual-article .hint {
    margin: var(--space-8) 0;
    padding: var(--space-4) var(--space-4) var(--space-3);
    border-top: .16rem solid var(--line-strong);
    background: var(--note-bg);
  }
  .manual-article .hint { background: var(--hint-bg); }
  .manual-article :where(.note, .hint) h4 { margin: 0 0 var(--space-2); color: var(--text); font-family: var(--font-display); font-size: .72rem; letter-spacing: .1em; text-transform: uppercase; }
  .manual-article :where(.note, .hint) ul { margin-bottom: 0; }
  .manual-article .menu, .manual-article .key, .manual-article .button { font-weight: 700; }
  .manual-article .related-topic { margin-top: var(--space-16); padding-top: var(--space-6); border-top: 1px solid var(--line-strong); }
  .manual-article .related-topic h3 { margin-top: 0; font-size: 1.25rem; }
  .manual-article .img-box, .manual-article figure { margin: var(--space-8) 0; }
  .manual-article .caption { color: var(--text-muted); font-size: .75em; }
}

@layer responsive {
  @media (hover: hover) {
    .quick-item:hover .arrow, .ruled-item:hover .arrow { transform: translateX(.25rem); }
    .quick-item:hover strong, .ruled-item:hover strong, .section-row:hover strong { color: var(--accent); }
    .search-result:hover { background: color-mix(in oklch, var(--surface-raised) 80%, transparent); }
    .hero-search:hover { background: var(--accent); color: var(--accent-ink); }
    .hero-search:hover svg { color: var(--accent-ink); }
    .hero-search:hover small { color: color-mix(in oklch, var(--accent-ink) 70%, var(--accent)); }
  }

  @media (max-width: 47.99rem) {
    .bottom-nav button { font-size: .75rem; }
    .hero-search small { font-size: .78rem; }
    .hero-meta { font-size: .78rem; }
    .section-heading p { font-size: .72rem; }
    .quick-item small, .ruled-item small { font-size: .78rem; }
    .section-row small { font-size: .75rem; }
    .home-footer { font-size: .72rem; }
    .search-status { font-size: .78rem; }
    .search-result small { font-size: .74rem; }
    .search-result p { font-size: .8rem; }
    .toc-content summary strong { font-size: .94rem; }
    .toc-content summary small { font-size: .72rem; }
    .toc-items button { font-size: .85rem; }
    .favorite-row small { font-size: .74rem; }
  }

  @media (min-width: 48rem) {
    .home-content { width: min(100%, 50rem); margin-inline: auto; }
    .hero { padding-inline: clamp(3rem, 10vw, 8rem); }
    .quick-item, .section-row { min-height: 5.25rem; }
    dialog:not(.image-dialog) {
      width: min(44rem, calc(100% - 3rem));
      height: min(50rem, calc(100dvh - 3rem));
      margin: auto;
      padding: 2rem;
      border: 1px solid var(--line-strong);
      box-shadow: var(--shadow-dialog);
    }
  }

  @media (min-width: 64rem) {
    .mobile-header, .bottom-nav { display: none; }
    .app-shell { display: grid; min-height: 100dvh; grid-template-columns: 20rem minmax(0, 1fr); }
    .desktop-rail {
      position: sticky;
      top: 0;
      display: flex;
      height: 100dvh;
      flex-direction: column;
      overflow: hidden;
      border-right: 1px solid oklch(28% 0.009 85);
      background: var(--rail);
      color: var(--rail-text);
    }
    .rail-brand { display: flex; min-height: 6.5rem; align-items: center; gap: 1.25rem; padding: 1.25rem 1.5rem; border-bottom: 1px solid oklch(28% 0.009 85); }
    .rail-brand img { width: 4.6rem; height: auto; }
    .rail-model { display: flex; min-width: 0; flex-direction: column; }
    .rail-model strong { font-family: var(--font-display); font-size: .86rem; letter-spacing: .06em; }
    .rail-model span { color: var(--rail-muted); font-family: var(--font-display); font-size: .52rem; letter-spacing: .1em; }
    .rail-search { display: grid; min-height: 4.2rem; grid-template-columns: 1.25rem 1fr auto; align-items: center; gap: .7rem; margin: 1.25rem; padding: 0 1rem; background: var(--rail-raised); color: var(--rail-text); text-align: left; }
    .rail-search span { font-size: .8rem; font-weight: 600; }
    .rail-search kbd { color: var(--rail-muted); font-family: var(--font-ui); font-size: .6rem; }
    .rail-nav { min-height: 0; flex: 1; overflow-y: auto; padding: 0 1.25rem 1rem; scrollbar-width: thin; scrollbar-color: oklch(34% 0.01 85) transparent; }
    .rail-home { display: flex; width: 100%; min-height: 3.5rem; align-items: center; justify-content: space-between; border-bottom: 1px solid oklch(28% 0.009 85); text-align: left; }
    .rail-home span { font-size: .78rem; font-weight: 700; }
    .rail-home small { color: var(--rail-muted); font-size: .5rem; letter-spacing: .1em; }
    .rail-home.active span { color: var(--accent); }
    .rail-sections summary { color: var(--rail-text); }
    .rail-sections summary span { font-size: .75rem; font-weight: 600; }
    .rail-sections summary small { margin-left: .35rem; color: var(--rail-muted); font-size: .58rem; }
    .rail-sections .toc-items button { min-height: 2.7rem; padding: .5rem .6rem; color: var(--rail-muted); font-size: .7rem; }
    .rail-sections .toc-items button.active { background: var(--accent); color: var(--accent-ink); }
    .rail-footer { border-top: 1px solid oklch(28% 0.009 85); padding: .75rem 1.25rem; }
    .rail-footer :where(button, a) { display: flex; width: 100%; min-height: 2.7rem; align-items: center; justify-content: space-between; color: var(--rail-muted); font-size: .64rem; text-decoration: none; }
    .home-view, .reader-view { padding-bottom: 0; }
    .hero { min-height: 44rem; padding: clamp(3rem, 6vw, 6rem); }
    .home-content { width: min(100%, 66rem); padding: var(--space-24) clamp(3rem, 6vw, 6rem); }
    .quick-list { display: grid; grid-template-columns: 1fr 1fr; column-gap: 3rem; }
    .section-index { display: grid; grid-template-columns: 1fr 1fr; column-gap: 3rem; border-top: 0; }
    .section-row:nth-child(-n+2) { border-top: 1px solid var(--line-strong); }
    .reader-toolbar { position: sticky; z-index: 20; top: 0; background: var(--bg); }
    .reader-shell { width: min(100%, 58rem); padding-top: var(--space-16); }
    .manual-article { --text-size: 1.05rem; }
    .manual-article .table-scroll { margin-inline: 0; padding-inline: 0; }
    .toast { right: 2rem; bottom: 2rem; left: auto; width: max-content; max-width: 24rem; }
  }

  @media (orientation: landscape) and (max-height: 32rem) and (max-width: 63.99rem) {
    .hero { min-height: auto; gap: var(--space-8); }
    .hero h1 { font-size: clamp(4rem, 16vh, 6rem); }
  }

  @media (pointer: coarse) {
    .toc-items button { min-height: 3.2rem; }
  }

  @media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  }

  @media print {
    .mobile-header, .desktop-rail, .bottom-nav, .reader-toolbar, .article-pager, .reading-progress { display: none !important; }
    .home-view { display: none !important; }
    .reader-view { display: block !important; }
    .reader-shell { width: auto; padding: 0; }
    body { background: white; color: black; }
    .manual-article a { color: black; }
  }
}