:root {
      color-scheme: light;
      --paper: #f1eee5;
      --paper-deep: #e6e1d5;
      --ink: #171916;
      --muted: #63665f;
      --line: #b8b6ad;
      --line-strong: #777a73;
      --white: #faf8f1;
      --transform: #155d5b;
      --trace: #1d4f87;
      --evaluation: #a34222;
      --feedback: #8a6118;
      --pass: #256b43;
      --fail: #a33c25;
      --unknown: #6b6d67;
      --sans: "Avenir Next", "Segoe UI", "Helvetica Neue", Arial, sans-serif;
      --serif: "Iowan Old Style", "Baskerville", "Times New Roman", serif;
      --mono: "SFMono-Regular", "Cascadia Code", "Roboto Mono", Consolas, monospace;
      --page: min(1480px, calc(100vw - 36px));
      --rail: 236px;
      --gutter: clamp(24px, 4vw, 72px);
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; scroll-padding-top: 28px; }
    body {
      margin: 0;
      background:
        linear-gradient(90deg, transparent 23px, rgba(23,25,22,.055) 24px, transparent 25px),
        var(--paper);
      color: var(--ink);
      font-family: var(--sans);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }
    button, a { font: inherit; }
    button { color: inherit; }
    a { color: inherit; }
    :focus-visible { outline: 3px solid var(--evaluation); outline-offset: 4px; }
    ::selection { background: #d7b765; color: var(--ink); }

    .sheet {
      width: var(--page);
      margin: 18px auto 56px;
      border: 1px solid var(--line-strong);
      background: var(--paper);
      box-shadow: 10px 14px 0 rgba(23,25,22,.08);
      position: relative;
    }
    .sheet::before {
      content: "";
      position: absolute;
      inset: 7px;
      border: 1px solid rgba(23,25,22,.12);
      pointer-events: none;
      z-index: 20;
    }
    .masthead {
      min-height: 64px;
      display: grid;
      grid-template-columns: var(--rail) 1fr auto;
      align-items: stretch;
      border-bottom: 2px solid var(--ink);
      position: relative;
      z-index: 21;
      background: var(--paper);
    }
    .brand {
      display: flex;
      align-items: center;
      gap: 11px;
      padding: 0 20px;
      border-right: 1px solid var(--line-strong);
      text-decoration: none;
      font-weight: 800;
      letter-spacing: -.02em;
    }
    .brand-mark {
      width: 29px;
      aspect-ratio: 1;
      border: 2px solid;
      display: grid;
      place-items: center;
      font: 800 11px/1 var(--mono);
      transform: rotate(-2deg);
    }
    .edition {
      display: flex;
      align-items: center;
      padding: 0 22px;
      font: 600 11px/1.2 var(--mono);
      letter-spacing: .1em;
      text-transform: uppercase;
      color: var(--muted);
    }
    .research-label {
      width: fit-content;
      display: grid;
      grid-template-columns: auto auto;
      margin: 0 0 22px;
      border: 1px solid var(--ink);
      background: var(--white);
      box-shadow: 4px 4px 0 var(--evaluation);
      transform: rotate(-.45deg);
      font: 800 9px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .1em;
    }
    .research-label b {
      padding: 9px 11px;
      background: var(--ink);
      color: var(--paper);
    }
    .research-label span {
      padding: 9px 12px;
      color: var(--evaluation);
    }
    .global-links {
      display: flex;
      border-left: 1px solid var(--line-strong);
    }
    .global-links a {
      display: flex;
      align-items: center;
      padding: 0 15px;
      border-right: 1px solid var(--line);
      text-decoration: none;
      font: 700 9px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .06em;
    }
    .global-links a:last-child { border-right: 0; }
    .global-links a:hover,
    .global-links a:focus-visible,
    .global-links a[aria-current="page"] { background: var(--ink); color: var(--paper); }

    .layout {
      display: grid;
      grid-template-columns: var(--rail) minmax(0, 1fr);
    }
    .toc {
      position: relative;
      border-right: 1px solid var(--line-strong);
    }
    .toc-inner {
      position: sticky;
      top: 18px;
      padding: 22px 18px 28px;
      max-height: calc(100vh - 36px);
      overflow-y: auto;
    }
    .toc-kicker,
    .eyebrow,
    .chapter-no,
    .micro-label {
      font: 700 10px/1.2 var(--mono);
      text-transform: uppercase;
      letter-spacing: .13em;
    }
    .toc-kicker { margin: 0 0 18px; color: var(--muted); }
    .toc ol { list-style: none; padding: 0; margin: 0; counter-reset: guide; }
    .toc li { border-top: 1px solid var(--line); counter-increment: guide; }
    .toc li:last-child { border-bottom: 1px solid var(--line); }
    .toc a {
      display: grid;
      grid-template-columns: 25px 1fr;
      gap: 7px;
      padding: 9px 2px;
      text-decoration: none;
      color: var(--muted);
      font: 600 11px/1.3 var(--mono);
    }
    .toc a::before { content: counter(guide, decimal-leading-zero); }
    .toc a:hover,
    .toc a.active { color: var(--ink); }
    .toc a.active { font-weight: 800; }
    .toc-key {
      margin-top: 24px;
      display: grid;
      gap: 7px;
      color: var(--muted);
      font: 600 10px/1.2 var(--mono);
    }
    .toc-key span { display: flex; align-items: center; gap: 8px; }
    .key-swatch { width: 15px; height: 5px; background: var(--ink); }
    .key-swatch.transform { background: var(--transform); }
    .key-swatch.trace { background: var(--trace); }
    .key-swatch.evaluation { background: var(--evaluation); }
    .key-swatch.feedback { background: var(--feedback); }

    main { min-width: 0; }
    .chapter {
      position: relative;
      padding: clamp(54px, 8vw, 112px) var(--gutter);
      border-bottom: 1px solid var(--line-strong);
      overflow: hidden;
    }
    .chapter:last-child { border-bottom: 0; }
    .chapter-header {
      display: grid;
      grid-template-columns: 78px minmax(0, 820px);
      gap: 18px;
      align-items: start;
      margin-bottom: 42px;
    }
    .chapter-no {
      color: var(--muted);
      padding-top: 9px;
      border-top: 4px solid var(--ink);
    }
    .chapter h2 {
      margin: 0;
      font: 500 clamp(38px, 5vw, 72px)/.98 var(--serif);
      letter-spacing: -.045em;
      text-wrap: balance;
    }
    .chapter-intro {
      max-width: 720px;
      margin: 0 0 34px 96px;
      color: #42453f;
      font-size: clamp(17px, 1.55vw, 21px);
      text-wrap: pretty;
    }
    .lede {
      font: 400 clamp(19px, 1.7vw, 25px)/1.45 var(--serif);
      max-width: 720px;
    }
    .annotation {
      font: 600 11px/1.45 var(--mono);
      color: var(--muted);
    }
    .rule-label {
      display: flex;
      align-items: center;
      gap: 12px;
      margin: 28px 0 14px;
      font: 700 10px/1.2 var(--mono);
      text-transform: uppercase;
      letter-spacing: .12em;
      color: var(--muted);
    }
    .rule-label::after { content: ""; height: 1px; background: var(--line); flex: 1; }

    /* Hero */
    .hero {
      min-height: calc(100vh - 83px);
      padding-top: clamp(38px, 5vw, 72px);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      background:
        repeating-linear-gradient(0deg, transparent 0 31px, rgba(23,25,22,.035) 31px 32px);
    }
    .hero-top { display: grid; grid-template-columns: minmax(0, 1fr) minmax(250px, .42fr); gap: 40px; }
    .eyebrow { color: var(--evaluation); margin: 0 0 18px; }
    .hero h1 {
      margin: 0;
      max-width: 790px;
      font: 500 clamp(54px, 7.4vw, 108px)/.88 var(--serif);
      letter-spacing: -.06em;
      text-wrap: balance;
    }
    .hero-note {
      align-self: end;
      max-width: 340px;
      border-top: 4px solid var(--ink);
      padding-top: 14px;
    }
    .hero-note p {
      margin: 0 0 18px;
      font-size: 17px;
      color: #3d403a;
    }
    .actions { display: flex; flex-wrap: wrap; gap: 9px; }
    .button {
      min-height: 44px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0 16px;
      border: 1px solid var(--ink);
      background: var(--ink);
      color: var(--paper);
      text-decoration: none;
      font: 700 11px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .button.secondary { background: transparent; color: var(--ink); }
    .button:hover { transform: translateY(-2px); box-shadow: 3px 3px 0 var(--evaluation); }

    .canonical {
      display: grid;
      grid-template-columns: repeat(9, auto);
      align-items: center;
      justify-content: start;
      gap: 8px;
      margin: 28px 0;
      overflow-x: auto;
      scrollbar-width: thin;
      padding-bottom: 5px;
    }
    .canonical span:not(.arrow) {
      white-space: nowrap;
      padding: 7px 9px;
      border: 1px solid var(--ink);
      font: 700 10px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .07em;
      background: var(--white);
    }
    .canonical .arrow { font: 16px var(--mono); }
    .canonical .t { border-bottom: 4px solid var(--transform) !important; }
    .canonical .tr { border-bottom: 4px solid var(--trace) !important; }
    .canonical .e { border-bottom: 4px solid var(--evaluation) !important; }
    .canonical .f { border-bottom: 4px solid var(--feedback) !important; }

    .hero-instrument {
      display: grid;
      grid-template-columns: minmax(420px, 1.35fr) minmax(330px, .85fr);
      border: 1px solid var(--ink);
      background: rgba(250,248,241,.75);
      min-height: 270px;
    }
    .graph-panel,
    .trace-panel { padding: 18px; min-width: 0; }
    .graph-panel { border-right: 1px solid var(--ink); }
    .panel-head {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 16px;
      margin-bottom: 18px;
      font: 700 10px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .11em;
    }
    .panel-head .live { color: var(--evaluation); }
    .hero-graph {
      display: grid;
      grid-template-columns: repeat(11, minmax(0, auto));
      align-items: center;
      gap: 5px;
      min-height: 114px;
      overflow-x: auto;
      padding: 8px 0 12px;
    }
    .graph-node {
      border: 1px solid var(--ink);
      background: var(--paper);
      min-height: 64px;
      min-width: 82px;
      padding: 9px;
      text-align: left;
      cursor: pointer;
      font: 700 10px/1.35 var(--mono);
      position: relative;
    }
    .graph-node small {
      display: block;
      margin-top: 6px;
      color: var(--muted);
      font: 600 8px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .graph-node[data-tone="transform"] { border-top: 5px solid var(--transform); }
    .graph-node[data-tone="evaluation"] { border-top: 5px solid var(--evaluation); }
    .graph-node[data-tone="feedback"] { border-top: 5px solid var(--feedback); }
    .graph-node.active {
      color: var(--white);
      background: var(--ink);
      transform: translateY(-3px);
      box-shadow: 3px 4px 0 var(--trace);
    }
    .graph-node.active small { color: #d4d2c9; }
    .graph-arrow { font: 16px/1 var(--mono); text-align: center; color: var(--line-strong); }
    .graph-legend {
      border-top: 1px solid var(--line);
      padding-top: 10px;
      display: flex;
      justify-content: space-between;
      gap: 15px;
      color: var(--muted);
      font: 600 9px/1.4 var(--mono);
    }
    .trace-list { display: grid; gap: 2px; }
    .trace-row {
      display: grid;
      grid-template-columns: 20px 1fr auto;
      gap: 8px;
      align-items: baseline;
      padding: 8px 7px;
      border-bottom: 1px solid var(--line);
      font: 600 10px/1.25 var(--mono);
      cursor: pointer;
    }
    .trace-row:last-child { border-bottom: 0; }
    .trace-row .status { font-weight: 900; }
    .trace-row .detail { color: var(--muted); text-align: right; }
    .trace-row.fail .status,
    .trace-row.fail .detail { color: var(--fail); }
    .trace-row.active { background: #ddd8cc; box-shadow: inset 4px 0 0 var(--trace); }
    .trace-foot {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 1px;
      background: var(--ink);
      border-top: 1px solid var(--ink);
      margin: 8px -18px -18px;
    }
    .trace-foot > div {
      background: var(--paper-deep);
      padding: 9px 17px;
      display: flex;
      justify-content: space-between;
      gap: 10px;
      font: 700 10px/1.2 var(--mono);
    }
    .trace-foot strong { color: var(--fail); text-transform: uppercase; }

    /* Problem */
    .failure-ledger {
      display: grid;
      grid-template-columns: 1fr 1fr;
      border-top: 2px solid var(--ink);
      margin-top: 44px;
    }
    .failure-item {
      min-height: 158px;
      padding: 19px 22px 28px 0;
      border-bottom: 1px solid var(--line);
      position: relative;
    }
    .failure-item:nth-child(odd) { border-right: 1px solid var(--line); padding-right: 28px; }
    .failure-item:nth-child(even) { padding-left: 28px; }
    .failure-item .index {
      display: block;
      margin-bottom: 24px;
      color: var(--evaluation);
      font: 800 11px/1 var(--mono);
    }
    .failure-item p { margin: 0; max-width: 360px; font: 500 20px/1.25 var(--serif); }
    .axiom {
      margin: 52px 0 0 96px;
      max-width: 860px;
      border-left: 10px solid var(--evaluation);
      padding: 8px 0 8px 27px;
      font: 500 clamp(30px, 4vw, 62px)/1.02 var(--serif);
      letter-spacing: -.035em;
    }

    /* Primitives */
    .primitive-register {
      display: grid;
      grid-template-columns: 1fr 1fr;
      border: 1px solid var(--ink);
      background: var(--white);
    }
    .primitive {
      min-height: 230px;
      padding: 22px;
      border-bottom: 1px solid var(--ink);
      position: relative;
    }
    .primitive:nth-child(odd) { border-right: 1px solid var(--ink); }
    .primitive:nth-last-child(-n+2) { border-bottom: 0; }
    .primitive .tab {
      display: inline-block;
      padding: 5px 7px;
      color: var(--white);
      font: 800 9px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .1em;
    }
    .primitive.transform .tab { background: var(--transform); }
    .primitive.trace .tab { background: var(--trace); }
    .primitive.evaluation .tab { background: var(--evaluation); }
    .primitive.feedback .tab { background: var(--feedback); }
    .primitive h3 { margin: 35px 0 12px; font: 500 34px/1 var(--serif); }
    .primitive p { margin: 0; max-width: 390px; color: var(--muted); font-size: 15px; }
    .primitive code { display: block; margin-top: 26px; font: 600 11px/1.4 var(--mono); color: var(--ink); }

    /* Progression */
    .progression {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 0;
      border-top: 1px solid var(--ink);
      border-bottom: 1px solid var(--ink);
      margin: 40px 0 55px;
    }
    .progression-step {
      min-height: 150px;
      padding: 16px;
      border-right: 1px solid var(--ink);
    }
    .progression-step:last-child { border-right: 0; }
    .progression-step b { display: block; font: 700 10px/1.2 var(--mono); color: var(--muted); }
    .progression-step span { display: block; margin-top: 34px; font: 500 19px/1.15 var(--serif); }
    .dag-study {
      display: grid;
      grid-template-columns: 1.1fr .9fr;
      border: 1px solid var(--ink);
      background: var(--white);
    }
    .dag-diagram { min-height: 330px; padding: 30px; border-right: 1px solid var(--ink); }
    .dag-grid {
      height: 245px;
      display: grid;
      grid-template-columns: 1fr 1fr 1fr;
      grid-template-rows: 1fr 1fr;
      align-items: center;
      justify-items: center;
      position: relative;
    }
    .dag-grid::before,
    .dag-grid::after {
      content: "";
      position: absolute;
      left: 22%;
      right: 22%;
      height: 1px;
      background: var(--ink);
      transform-origin: center;
      z-index: 0;
    }
    .dag-grid::before { top: 37%; transform: rotate(-21deg); }
    .dag-grid::after { bottom: 37%; transform: rotate(21deg); }
    .dag-box {
      position: relative;
      z-index: 1;
      padding: 12px;
      border: 1px solid var(--ink);
      background: var(--paper);
      font: 700 10px/1.3 var(--mono);
      text-align: center;
    }
    .dag-input { grid-row: 1 / 3; grid-column: 1; }
    .dag-physics { grid-row: 1; grid-column: 2; border-top: 5px solid var(--transform); }
    .dag-empirical { grid-row: 2; grid-column: 2; border-top: 5px solid var(--transform); }
    .dag-reconcile { grid-row: 1 / 3; grid-column: 3; border-top: 5px solid var(--evaluation); }
    .run-demo { padding: 26px; }
    .run-demo h3 { margin: 0 0 7px; font: 500 28px/1 var(--serif); }
    .run-demo p { color: var(--muted); font-size: 13px; margin: 0 0 20px; }
    .run-console {
      min-height: 142px;
      padding: 14px;
      background: var(--ink);
      color: #efeee8;
      font: 600 11px/1.65 var(--mono);
      white-space: pre-wrap;
    }
    .run-console .bad { color: #ff9476; }
    .run-console .good { color: #8fd2a8; }
    .run-button {
      width: 100%;
      margin-top: 10px;
      border: 1px solid var(--ink);
      background: var(--paper);
      min-height: 43px;
      cursor: pointer;
      font: 800 10px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .09em;
    }
    .run-button:hover { background: var(--feedback); color: white; }

    /* System scan */
    .scan-grid {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      border: 1px solid var(--ink);
      background: var(--white);
    }
    .scan-item {
      min-height: 170px;
      padding: 20px;
      border-bottom: 1px solid var(--line);
    }
    .scan-item:nth-child(odd) { border-right: 1px solid var(--line); }
    .scan-item:nth-last-child(-n+2) { border-bottom: 0; }
    .scan-item b {
      display: block;
      margin-bottom: 25px;
      color: var(--evaluation);
      font: 800 10px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .09em;
    }
    .scan-item h3 { margin: 0 0 9px; font: 500 25px/1 var(--serif); }
    .scan-item p { margin: 0; color: var(--muted); font-size: 14px; }
    .scan-note {
      margin: 18px 0 0;
      padding: 14px 17px;
      border: 1px dashed var(--line-strong);
      font: 650 11px/1.5 var(--mono);
    }

    /* Architecture laboratory */
    .architecture-tabs {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      border: 1px solid var(--ink);
    }
    .architecture-tabs button {
      min-height: 70px;
      padding: 11px;
      border: 0;
      border-right: 1px solid var(--ink);
      background: transparent;
      cursor: pointer;
      text-align: left;
      font: 800 10px/1.35 var(--mono);
      text-transform: uppercase;
      letter-spacing: .05em;
    }
    .architecture-tabs button:last-child { border-right: 0; }
    .architecture-tabs button[aria-selected="true"] {
      background: var(--ink);
      color: var(--paper);
      box-shadow: inset 0 -5px 0 var(--evaluation);
    }
    .architecture-board {
      display: grid;
      grid-template-columns: minmax(0, 1.45fr) minmax(300px, .75fr);
      border: 1px solid var(--ink);
      border-top: 0;
      background: var(--white);
    }
    .architecture-canvas { min-width: 0; padding: 24px; border-right: 1px solid var(--ink); }
    .architecture-title {
      display: flex;
      justify-content: space-between;
      gap: 15px;
      margin-bottom: 24px;
      font: 750 10px/1.3 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .architecture-title span:last-child { color: var(--muted); }
    .architecture-flow {
      min-height: 190px;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: center;
      gap: 9px;
      padding: 24px 8px;
      border-top: 1px solid var(--line);
      border-bottom: 1px solid var(--line);
    }
    .arch-node {
      min-width: 108px;
      max-width: 150px;
      padding: 12px;
      border: 1px solid var(--ink);
      background: var(--paper);
      cursor: pointer;
      font: 750 10px/1.3 var(--mono);
      text-align: left;
    }
    .arch-node small {
      display: block;
      margin-top: 8px;
      color: var(--muted);
      font: 650 8px/1.25 var(--mono);
      text-transform: uppercase;
    }
    .arch-node.active { color: var(--white); background: var(--ink); box-shadow: 3px 4px 0 var(--trace); }
    .arch-node.active small { color: #d5d4cc; }
    .arch-node[data-kind="model"] { border-top: 5px solid var(--evaluation); }
    .arch-node[data-kind="tool"] { border-top: 5px solid var(--trace); }
    .arch-node[data-kind="deterministic"] { border-top: 5px solid var(--transform); }
    .arch-node[data-kind="human"] { border-top: 5px solid var(--feedback); }
    .arch-arrow { color: var(--line-strong); font: 700 15px/1 var(--mono); }
    .architecture-annotation {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1px;
      margin-top: 14px;
      background: var(--line);
    }
    .architecture-annotation div { min-height: 82px; padding: 12px; background: var(--paper); }
    .architecture-annotation b {
      display: block;
      margin-bottom: 8px;
      color: var(--muted);
      font: 800 8px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .architecture-annotation span { font-size: 12px; line-height: 1.4; }
    .boundary-register { padding: 24px; }
    .boundary-register h3 { margin: 0 0 20px; font: 500 27px/1 var(--serif); }
    .boundary-list { margin: 0; }
    .boundary-list div { padding: 12px 0; border-top: 1px solid var(--line); }
    .boundary-list dt {
      margin-bottom: 5px;
      color: var(--muted);
      font: 800 9px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .boundary-list dd { margin: 0; font-size: 13px; line-height: 1.45; }
    .dag-warning {
      margin: 20px 0 0;
      padding: 13px;
      border-left: 6px solid var(--feedback);
      background: var(--paper-deep);
      font: 700 10px/1.5 var(--mono);
    }

    /* Relation failures */
    .relation-studies { border-top: 2px solid var(--ink); }
    .relation-study {
      display: grid;
      grid-template-columns: 170px 1fr 1fr;
      border-bottom: 1px solid var(--line);
      min-height: 135px;
    }
    .relation-study > div { padding: 20px; border-right: 1px solid var(--line); }
    .relation-study > div:last-child { border-right: 0; }
    .relation-study h3 { margin: 0; font: 500 24px/1 var(--serif); }
    .relation-study b {
      display: block;
      margin-bottom: 10px;
      font: 800 9px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .relation-study p { margin: 0; color: var(--muted); font-size: 14px; }
    .relation-study .broken b,
    .relation-study .broken p { color: var(--fail); }

    /* Terminal */
    .terminal {
      border: 1px solid #22241f;
      background: #20231f;
      color: #f1efe5;
      box-shadow: 7px 7px 0 var(--line);
    }
    .terminal-bar {
      display: flex;
      justify-content: space-between;
      padding: 12px 16px;
      border-bottom: 1px solid #666a62;
      color: #b8bbb4;
      font: 700 9px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .1em;
    }
    .terminal pre {
      margin: 0;
      padding: clamp(20px, 4vw, 42px);
      overflow-x: auto;
      font: 600 clamp(11px, 1.25vw, 15px)/1.65 var(--mono);
    }
    .terminal-caption {
      display: grid;
      grid-template-columns: 1.2fr .8fr;
      margin-top: 25px;
      gap: 35px;
    }
    .terminal-caption p { margin: 0; }

    /* Examples */
    .system-atlas {
      display: grid;
      grid-template-columns: 1fr 1fr;
      border-top: 2px solid var(--ink);
    }
    .system-entry {
      min-height: 280px;
      padding: 24px 0 30px;
      border-bottom: 1px solid var(--line-strong);
    }
    .system-entry:nth-child(odd) { border-right: 1px solid var(--line-strong); padding-right: 28px; }
    .system-entry:nth-child(even) { padding-left: 28px; }
    .system-entry h3 { margin: 0 0 27px; font: 500 28px/1 var(--serif); }
    .mini-flow { display: grid; gap: 6px; }
    .mini-flow span {
      display: grid;
      grid-template-columns: 24px 1fr;
      align-items: center;
      font: 650 11px/1.35 var(--mono);
    }
    .mini-flow span::before { content: "↓"; color: var(--transform); font-size: 15px; }
    .mini-flow span:first-child::before { content: "●"; font-size: 9px; }
    .domain-note {
      margin-top: 34px;
      padding: 18px;
      border: 1px dashed var(--line-strong);
      font: 600 12px/1.5 var(--mono);
    }

    /* Compare */
    .compare-control {
      display: grid;
      grid-template-columns: 1fr 1fr;
      border: 1px solid var(--ink);
      margin-bottom: 1px;
    }
    .compare-control button {
      min-height: 56px;
      border: 0;
      background: transparent;
      cursor: pointer;
      font: 800 11px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .compare-control button + button { border-left: 1px solid var(--ink); }
    .compare-control button[aria-selected="true"] { background: var(--ink); color: var(--paper); }
    .comparison-sheet {
      border: 1px solid var(--ink);
      background: var(--white);
    }
    .comparison-head,
    .comparison-row {
      display: grid;
      grid-template-columns: minmax(150px, 1.1fr) 1fr 1fr;
    }
    .comparison-head > div,
    .comparison-row > div { padding: 15px 18px; border-right: 1px solid var(--line); }
    .comparison-head > div:last-child,
    .comparison-row > div:last-child { border-right: 0; }
    .comparison-head {
      border-bottom: 2px solid var(--ink);
      font: 800 10px/1.3 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .comparison-row {
      border-bottom: 1px solid var(--line);
      min-height: 58px;
      align-items: center;
      font-size: 14px;
    }
    .comparison-row:last-child { border-bottom: 0; }
    .comparison-row .metric { font: 700 11px/1.3 var(--mono); color: var(--muted); }
    .comparison-row .selected { background: #e2ddd0; font-weight: 750; }
    .comparison-row small { display: block; color: var(--muted); margin-top: 3px; }
    .compare-provenance {
      display: grid;
      grid-template-columns: auto 1fr;
      gap: 15px;
      margin-top: 18px;
      color: var(--muted);
      font: 600 10px/1.55 var(--mono);
    }
    .compare-provenance b { color: var(--ink); }

    /* Philosophy */
    .theory-stack { border-top: 2px solid var(--ink); }
    .theory-row {
      display: grid;
      grid-template-columns: 180px 1fr 1fr;
      gap: 22px;
      padding: 20px 0;
      border-bottom: 1px solid var(--line);
      align-items: baseline;
    }
    .theory-row h3 { margin: 0; font: 500 23px/1.15 var(--serif); }
    .theory-row p { margin: 0; color: var(--muted); font-size: 14px; }
    .theory-row code { font: 700 11px/1.4 var(--mono); }
    .surface {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin: 38px 0;
    }
    .surface code { padding: 9px 11px; border: 1px solid var(--ink); background: var(--white); font: 700 12px var(--mono); }

    /* Code */
    .code-frame { border: 1px solid var(--ink); background: #20231f; color: #f3f0e6; }
    .code-tabs {
      display: flex;
      justify-content: space-between;
      border-bottom: 1px solid #666a62;
    }
    .tab-group { display: flex; }
    .code-tabs button {
      border: 0;
      border-right: 1px solid #666a62;
      min-height: 48px;
      padding: 0 19px;
      background: transparent;
      color: #b6bab1;
      cursor: pointer;
      font: 800 10px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .code-tabs button[aria-selected="true"] { color: #fff; background: #30342e; box-shadow: inset 0 -4px 0 #d58a45; }
    .code-tabs .copy { border-left: 1px solid #666a62; border-right: 0; }
    .code-panel { display: none; }
    .code-panel.active { display: block; }
    .code-panel pre {
      margin: 0;
      padding: clamp(18px, 4vw, 38px);
      overflow: auto;
      min-height: 390px;
      font: 600 clamp(11px, 1.15vw, 14px)/1.65 var(--mono);
      tab-size: 2;
    }
    .code-comment { color: #a4a99d; }
    .code-key { color: #efab72; }
    .code-str { color: #96c6a7; }

    /* Closing */
    .closing {
      min-height: 670px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      background: var(--ink);
      color: var(--paper);
    }
    .closing .chapter-no { color: #aaa99f; border-color: var(--paper); }
    .closing h2 { max-width: 900px; font-size: clamp(52px, 7vw, 102px); }
    .closing-bottom {
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 32px;
      align-items: end;
    }
    .closing-bottom p { max-width: 610px; margin: 0; color: #c5c4bb; font-size: 18px; }
    .closing .button { border-color: var(--paper); background: var(--paper); color: var(--ink); }
    .closing .button.secondary { background: transparent; color: var(--paper); }
    .folio {
      margin-top: 55px;
      padding-top: 14px;
      border-top: 1px solid #55584f;
      display: flex;
      justify-content: space-between;
      color: #979a91;
      font: 600 9px/1 var(--mono);
      text-transform: uppercase;
      letter-spacing: .1em;
    }

    @media (max-width: 980px) {
      :root { --rail: 190px; --gutter: 32px; }
      .hero-top { grid-template-columns: 1fr; }
      .hero-note { align-self: start; max-width: 600px; }
      .hero-instrument { grid-template-columns: 1fr; }
      .graph-panel { border-right: 0; border-bottom: 1px solid var(--ink); }
      .dag-study { grid-template-columns: 1fr; }
      .dag-diagram { border-right: 0; border-bottom: 1px solid var(--ink); }
      .architecture-board { grid-template-columns: 1fr; }
      .architecture-canvas { border-right: 0; border-bottom: 1px solid var(--ink); }
      .theory-row { grid-template-columns: 150px 1fr; }
      .theory-row code { grid-column: 2; }
    }

    @media (max-width: 720px) {
      :root { --page: calc(100vw - 16px); --gutter: 20px; }
      body { background: var(--paper-deep); }
      .sheet { margin: 8px auto 24px; box-shadow: 4px 5px 0 rgba(23,25,22,.08); }
      .masthead { grid-template-columns: 1fr auto; min-height: 56px; }
      .brand { border-right: 0; padding: 0 14px; }
      .edition { display: none; }
      .global-links { overflow-x: auto; }
      .global-links a { min-width: 66px; padding: 0 10px; justify-content: center; }
      .global-links a:nth-child(n+3) { display: none; }
      .layout { display: block; }
      .toc {
        border-right: 0;
        border-bottom: 1px solid var(--ink);
        overflow-x: auto;
        position: sticky;
        top: 0;
        z-index: 18;
        background: var(--paper);
      }
      .toc-inner { position: static; padding: 0; max-height: none; overflow: visible; }
      .toc-kicker, .toc-key { display: none; }
      .toc ol { display: flex; width: max-content; }
      .toc li { border-top: 0; border-right: 1px solid var(--line); }
      .toc li:last-child { border-bottom: 0; }
      .toc a { grid-template-columns: auto; padding: 11px 13px; font-size: 9px; }
      .toc a::before { display: none; }
      .chapter { padding: 54px var(--gutter); }
      .chapter-header { grid-template-columns: 45px 1fr; gap: 13px; margin-bottom: 30px; }
      .chapter h2 { font-size: clamp(37px, 12vw, 56px); }
      .chapter-intro, .axiom { margin-left: 0; }
      .hero { min-height: auto; padding-top: 38px; }
      .hero > div:first-child { display: flex; flex-direction: column; }
      .hero-top { display: contents; }
      .hero-top > div:first-child { order: 1; }
      .canonical {
        order: 2;
        grid-template-columns: repeat(5, minmax(0, 1fr));
        margin: 26px 0;
        padding: 0;
        gap: 4px;
        overflow: visible;
      }
      .canonical .arrow { display: none; }
      .canonical span:not(.arrow) {
        min-width: 0;
        padding: 7px 3px;
        white-space: normal;
        text-align: center;
        font-size: 7px;
        letter-spacing: .02em;
      }
      .hero-note { order: 3; }
      .hero h1 { font-size: clamp(48px, 14vw, 62px); line-height: .82; }
      .research-label { grid-template-columns: 1fr; }
      .research-label b, .research-label span { padding: 8px 10px; }
      .hero-instrument { min-height: 0; }
      .graph-panel, .trace-panel { padding: 14px; }
      .hero-graph { grid-template-columns: repeat(11, max-content); }
      .graph-legend { flex-direction: column; }
      .trace-foot { margin: 8px -14px -14px; }
      .failure-ledger,
      .primitive-register,
      .system-atlas { grid-template-columns: 1fr; }
      .failure-item:nth-child(odd),
      .primitive:nth-child(odd),
      .system-entry:nth-child(odd) { border-right: 0; padding-right: 0; }
      .failure-item:nth-child(even),
      .system-entry:nth-child(even) { padding-left: 0; }
      .primitive { border-right: 0 !important; border-bottom: 1px solid var(--ink) !important; }
      .primitive:last-child { border-bottom: 0 !important; }
      .scan-grid { grid-template-columns: 1fr; }
      .scan-item { border-right: 0 !important; border-bottom: 1px solid var(--line) !important; }
      .scan-item:last-child { border-bottom: 0 !important; }
      .architecture-tabs { grid-template-columns: 1fr 1fr; }
      .architecture-tabs button:nth-child(2) { border-right: 0; }
      .architecture-tabs button:nth-child(-n+2) { border-bottom: 1px solid var(--ink); }
      .architecture-flow { justify-content: flex-start; overflow-x: auto; flex-wrap: nowrap; }
      .architecture-annotation { grid-template-columns: 1fr; }
      .relation-study { grid-template-columns: 1fr; }
      .relation-study > div { border-right: 0; border-bottom: 1px solid var(--line); }
      .relation-study > div:last-child { border-bottom: 0; }
      .progression { grid-template-columns: 1fr; }
      .progression-step { min-height: 92px; border-right: 0; border-bottom: 1px solid var(--ink); display: grid; grid-template-columns: 40px 1fr; gap: 15px; }
      .progression-step:last-child { border-bottom: 0; }
      .progression-step span { margin-top: 0; }
      .dag-diagram { padding: 15px; min-height: 290px; }
      .dag-box { font-size: 8px; }
      .terminal-caption { grid-template-columns: 1fr; }
      .comparison-head,
      .comparison-row { grid-template-columns: 110px minmax(0, 1fr) minmax(0, 1fr); }
      .comparison-head > div,
      .comparison-row > div { padding: 11px 8px; overflow-wrap: anywhere; }
      .comparison-head { font-size: 8px; }
      .comparison-row { font-size: 12px; }
      .compare-provenance { grid-template-columns: 1fr; }
      .theory-row { grid-template-columns: 1fr; }
      .theory-row code { grid-column: auto; }
      .code-tabs button { padding: 0 11px; }
      .code-panel pre { min-height: 0; }
      .closing { min-height: 600px; }
      .closing-bottom { grid-template-columns: 1fr; }
    }

    @media (prefers-reduced-motion: reduce) {
      html { scroll-behavior: auto; }
      *, *::before, *::after {
        animation-duration: .01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: .01ms !important;
      }
      .button:hover, .graph-node.active { transform: none; }
    }