:root {
      --ink: #f3f0e8;
      --muted: #a9b1af;
      --dim: #727c7a;
      --bg: #0b1112;
      --panel: #121a1b;
      --panel-2: #172122;
      --line: #2a3636;
      --cyan: #57d9d0;
      --coral: #ff7a66;
      --yellow: #e8c766;
      --black: #071011;
      --radius: 18px;
    }
    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      min-width: 0;
      background: var(--bg);
      color: var(--ink);
      font-family: "IBM Plex Sans", sans-serif;
      font-size: 16px;
      line-height: 1.55;
    }
    button, a { -webkit-tap-highlight-color: transparent; }
    button { font: inherit; }
    a { color: var(--cyan); text-underline-offset: 3px; }
    .page { width: min(1180px, calc(100% - 40px)); margin: 0 auto; padding: 56px 0 80px; }
    .intro {
      display: grid;
      grid-template-columns: minmax(0, 1.25fr) minmax(250px, .75fr);
      gap: 56px;
      align-items: end;
      padding: 12px 0 48px;
      border-bottom: 1px solid var(--line);
    }
    .eyebrow, .micro {
      margin: 0 0 14px;
      font: 500 11px/1.25 "IBM Plex Mono", monospace;
      letter-spacing: .14em;
      text-transform: uppercase;
      color: var(--cyan);
    }
    /* Small plain-language gloss under a section header (e.g. the
       stated-directly vs implied distinction on claim panels). */
    .lab-gloss {
      margin: -8px 0 10px;
      font-size: 12.5px;
      line-height: 1.45;
      color: var(--muted);
      max-width: 640px;
    }
    h1 {
      max-width: 760px;
      margin: 0;
      font: 650 clamp(42px, 6.5vw, 76px)/.98 "Source Serif 4", serif;
      letter-spacing: -.035em;
    }
    .dek {
      margin: 0 0 3px;
      max-width: 480px;
      color: #c3cac7;
      font-size: 18px;
    }
    .intro-note { margin: 14px 0 0; color: var(--dim); font-size: 13px; }
    .workspace {
      display: grid;
      grid-template-columns: minmax(0, 1.65fr) minmax(270px, .72fr);
      gap: 28px;
      padding-top: 30px;
      align-items: start;
    }
    .quiz-card {
      position: relative;
      min-height: 530px;
      padding: clamp(26px, 4vw, 52px);
      border: 1px solid var(--line);
      border-radius: 28px 6px 28px 6px;
      background: var(--panel);
      overflow: hidden;
    }
    .quiz-card::after {
      content: "";
      position: absolute;
      width: 210px; height: 210px;
      right: -120px; top: -120px;
      border: 1px solid #274543;
      border-radius: 50%;
      box-shadow: 0 0 0 34px rgba(87,217,208,.025), 0 0 0 68px rgba(87,217,208,.02);
      pointer-events: none;
    }
    .start-screen, .question-screen, .result-screen { position: relative; z-index: 1; }
    .start-screen { display: grid; min-height: 425px; align-content: space-between; }
    .start-copy h2, .question-screen h2, .result-screen h2 {
      margin: 0;
      font-family: "Source Serif 4", serif;
      letter-spacing: -.025em;
    }
    .start-copy h2 { max-width: 680px; font-size: clamp(32px, 4.5vw, 52px); line-height: 1.04; }
    .start-copy p { max-width: 650px; margin: 22px 0 0; color: var(--muted); font-size: 17px; }
    .start-meta { display: flex; flex-wrap: wrap; gap: 10px 24px; margin: 28px 0 34px; color: var(--muted); font: 13px/1.4 "IBM Plex Mono", monospace; }
    .start-meta span::before { content: "•"; color: var(--coral); margin-right: 8px; }
    .primary, .answer-btn, .text-btn {
      border: 0;
      cursor: pointer;
      transition: background .18s ease, color .18s ease, border-color .18s ease, transform .18s ease;
    }
    .primary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      width: fit-content;
      padding: 15px 22px;
      border-radius: 5px 14px 5px 14px;
      background: var(--cyan);
      color: var(--black);
      font-weight: 600;
    }
    .primary:hover { background: #78e8e0; transform: translateY(-1px); }
    .primary .arrow { font-family: "IBM Plex Mono", monospace; }
    .question-top { display: flex; justify-content: space-between; gap: 20px; align-items: center; margin-bottom: 48px; }
    .count-label { color: var(--muted); font: 12px/1.2 "IBM Plex Mono", monospace; }
    .count-label strong { color: var(--cyan); font-weight: 500; }
    .progress { width: min(220px, 45%); height: 3px; background: #253031; overflow: hidden; }
    .progress > span { display: block; height: 100%; width: 0; background: var(--coral); transition: width .25s ease; }
    .question-screen h2 { max-width: 720px; font-size: clamp(29px, 4.2vw, 48px); line-height: 1.1; }
    .question-context { margin: 16px 0 30px; max-width: 700px; color: var(--muted); }
    .answers { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
    .answer-btn {
      position: relative;
      min-height: 118px;
      padding: 22px;
      text-align: left;
      border: 1px solid #344242;
      border-radius: 5px 17px 5px 17px;
      background: var(--panel-2);
      color: var(--ink);
      font-weight: 600;
    }
    .answer-btn small { display: block; margin-top: 8px; color: var(--muted); font-weight: 400; line-height: 1.4; }
    .answer-btn:hover { border-color: var(--cyan); background: #192627; }
    .question-actions { display: flex; justify-content: space-between; gap: 16px; margin-top: 22px; }
    .question-action-left { display: flex; flex-wrap: wrap; align-items: center; gap: 16px; }
    .text-btn { padding: 7px 0; background: transparent; color: var(--muted); font-size: 14px; border-bottom: 1px solid transparent; }
    .text-btn:hover { color: var(--ink); border-color: var(--dim); }
    .copy-progress-btn { color: var(--cyan); }
    .copy-status { min-width: 1px; color: var(--yellow); font: 11px/1.3 "IBM Plex Mono", monospace; }
    .explainer { margin-top: 14px; border-top: 1px solid #283435; }
    .explainer summary { width: fit-content; padding: 14px 0 2px; cursor: pointer; color: var(--cyan); font: 500 13px/1.4 "IBM Plex Mono", monospace; list-style: none; }
    .explainer summary::-webkit-details-marker { display: none; }
    .explainer summary::after { content: "+"; display: inline-block; margin-left: 9px; color: var(--coral); }
    .explainer[open] summary::after { content: "−"; }
    .explainer-body { max-width: 760px; padding: 10px 0 4px; color: #c3cac7; font-size: 14px; }
    .explainer-body p { margin: 0 0 14px; }
    .explainer-body strong { color: var(--ink); font-weight: 600; }
    .explainer-points { display: grid; gap: 10px; margin: 0; padding: 0; list-style: none; }
    .explainer-points li { position: relative; padding-left: 18px; }
    .explainer-points li::before { content: ""; position: absolute; left: 0; top: .68em; width: 6px; height: 6px; border-radius: 50%; background: var(--coral); }
    .explainer-points strong { margin-right: 4px; }
    .jargon-defs { color: var(--muted); }
    .explainer-contrast { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin: 18px 0 12px; }
    .explainer-example { padding: 13px 14px; border: 1px solid #30403f; background: #101819; color: var(--muted); line-height: 1.45; }
    .explainer-example strong { display: block; margin-bottom: 5px; color: var(--cyan); font: 500 11px/1.3 "IBM Plex Mono", monospace; letter-spacing: .08em; text-transform: uppercase; }
    .explainer-foot { color: var(--dim); font-size: 12px; }
    @media (max-width: 540px) { .explainer-contrast { grid-template-columns: 1fr; } }
    .rail { border-top: 3px solid var(--cyan); background: #0e1516; }
    .rail-inner { padding: 24px 22px 20px; border: 1px solid var(--line); border-top: 0; }
    .survivor-number { margin: 3px 0 0; font: 650 58px/1 "Source Serif 4", serif; letter-spacing: -.04em; }
    .survivor-number span { color: var(--dim); font-size: 28px; }
    .rail p { margin: 10px 0 22px; color: var(--muted); font-size: 14px; }
    .survivor-list { display: grid; gap: 18px; max-height: 440px; overflow: auto; scrollbar-color: #3c4a49 transparent; }
    .survivor-group { --family: var(--cyan); }
    .survivor-group h3 { display: flex; align-items: center; gap: 8px; margin: 0 0 3px; color: #e6ebe8; font: 500 11px/1.35 "IBM Plex Mono", monospace; letter-spacing: .07em; text-transform: uppercase; }
    .family-dot { flex: 0 0 auto; width: 8px; height: 8px; border-radius: 50%; background: var(--family); box-shadow: 0 0 0 2px color-mix(in srgb, var(--family) 22%, transparent); }
    .survivor-group-note { margin: 0 0 5px !important; color: var(--dim) !important; font-size: 11px !important; }
    .survivor-item { --family: var(--cyan); display: grid; grid-template-columns: 22px 1fr; gap: 9px; padding: 9px 0; border-top: 1px solid #202b2c; color: #d4d8d5; font-size: 13px; line-height: 1.35; }
    .survivor-item .n { display: grid; place-items: center; align-self: start; width: 20px; height: 20px; border-radius: 50%; background: var(--family); color: var(--family-ink, #071011); font: 500 10px/1 "IBM Plex Mono", monospace; }
    .survivor-item .theory-name { min-width: 0; }
    .rail-note { padding: 14px 22px; border: 1px solid var(--line); border-top: 0; color: var(--dim); font-size: 12px; }
    .result-screen { display: none; }
    .result-label { color: var(--coral); }
    .result-screen h2 { max-width: 760px; font-size: clamp(36px, 5vw, 62px); line-height: 1; }
    .result-link { color: var(--ink); text-decoration: none; }
    .result-link:hover, .result-link:focus-visible { color: var(--cyan); }
    .result-link .result-arrow { display: inline-block; margin-left: .12em; color: var(--cyan); font: 400 .48em/1 "IBM Plex Mono", monospace; vertical-align: .35em; }
    .source-note { margin: 11px 0 0; color: var(--dim); font-size: 12px; }
    .source-note a { color: var(--cyan); }
    .category { display: inline-block; margin: 17px 0 0; padding: 6px 10px; border: 0; border-radius: 999px; background: var(--family, #3b4949); color: var(--family-ink, #071011); font: 500 11px/1.2 "IBM Plex Mono", monospace; text-transform: uppercase; letter-spacing: .08em; }
    .result-summary { max-width: 740px; margin: 25px 0 0; color: #d8dcda; font-size: 18px; }
    .result-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; margin-top: 30px; }
    .result-block { padding-top: 14px; border-top: 1px solid #374444; }
    .result-block h3 { margin: 0 0 8px; color: var(--cyan); font: 500 11px/1.3 "IBM Plex Mono", monospace; text-transform: uppercase; letter-spacing: .12em; }
    .result-block p { margin: 0; color: var(--muted); font-size: 14px; }
    .alternatives { margin-top: 28px; }
    .alt-chips { display: grid; gap: 18px; margin-top: 10px; }
    .alt-group { --family: var(--cyan); }
    .alt-group h4 { display: flex; align-items: center; gap: 8px; margin: 0 0 7px; color: #e4e9e6; font: 500 11px/1.35 "IBM Plex Mono", monospace; letter-spacing: .07em; text-transform: uppercase; }
    .alt-group-list { display: flex; flex-wrap: wrap; gap: 8px; }
    .alt-chip { padding: 7px 10px; border: 1px solid color-mix(in srgb, var(--family) 68%, #334140); color: #dce2df; font-size: 12px; text-decoration: none; }
    .alt-chip:first-child { background: color-mix(in srgb, var(--family) 13%, transparent); }
    .result-actions { display: flex; flex-wrap: wrap; gap: 18px; align-items: center; margin-top: 34px; }
    .method { margin-top: 32px; padding: 42px 0 0; border-top: 1px solid var(--line); display: grid; grid-template-columns: 1fr 1fr; gap: 42px; }
    .method h2 { margin: 0; font: 500 27px/1.1 "Source Serif 4", serif; }
    .method p { margin: 12px 0 0; color: var(--muted); font-size: 14px; }
    .legend { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
    .legend div { --family: var(--coral); display: flex; align-items: center; gap: 10px; padding: 12px 14px; background: #101718; color: #c2c9c6; font-size: 13px; }
    .legend div::before { content: ""; flex: 0 0 auto; width: 9px; height: 9px; border-radius: 50%; background: var(--family); }
    footer { margin-top: 42px; padding-top: 20px; border-top: 1px solid var(--line); color: var(--dim); font-size: 12px; }
    .hidden { display: none !important; }
    @media (max-width: 820px) {
      .page { width: min(100% - 28px, 700px); padding: 30px 0 56px; }
      .intro { grid-template-columns: 1fr; gap: 20px; padding-bottom: 34px; }
      .dek { font-size: 16px; }
      .workspace { grid-template-columns: 1fr; }
      .quiz-card { min-height: 560px; padding: 26px 21px; border-radius: 22px 5px 22px 5px; }
      .start-screen { min-height: 500px; }
      .answers { grid-template-columns: 1fr; }
      .answer-btn { min-height: 102px; }
      .question-top { margin-bottom: 36px; }
      .rail { order: 2; }
      .survivor-list { max-height: 235px; }
      .method { grid-template-columns: 1fr; gap: 24px; }
    }
    @media (max-width: 480px) {
      h1 { font-size: 43px; }
      .start-copy h2 { font-size: 34px; }
      .question-screen h2 { font-size: 30px; }
      .question-top { align-items: flex-start; }
      .progress { margin-top: 7px; }
      .question-actions { align-items: flex-start; flex-direction: column; gap: 8px; }
      .result-grid { grid-template-columns: 1fr; gap: 18px; }
      .legend { grid-template-columns: 1fr; }
    }
    @media (prefers-reduced-motion: reduce) { * { scroll-behavior: auto !important; transition: none !important; } }

    /* Claims lab: inspect the entailment graph and try the DAG-driven quiz. */
    .claims-lab {
      margin-top: 64px;
      padding-top: 48px;
      border-top: 1px solid var(--line);
    }
    .lab-head {
      display: flex;
      justify-content: space-between;
      align-items: end;
      gap: 28px;
      flex-wrap: wrap;
      margin-bottom: 28px;
    }
    .lab-head h2 {
      margin: 0 0 12px;
      font: 650 clamp(30px, 4vw, 46px)/1.05 "Source Serif 4", serif;
      letter-spacing: -.02em;
    }
    .lab-head .dek { max-width: 560px; }
    .lab-tabs { display: flex; gap: 8px; }
    .lab-tab {
      padding: 10px 18px;
      border: 1px solid var(--line);
      border-radius: 999px;
      background: transparent;
      color: var(--muted);
      cursor: pointer;
    }
    .lab-tab.active {
      background: var(--cyan);
      border-color: var(--cyan);
      color: var(--black);
      font-weight: 600;
    }
    .lab-pane {
      border: 1px solid var(--line);
      border-radius: 28px 6px 28px 6px;
      background: var(--panel);
      padding: clamp(22px, 3.5vw, 40px);
    }
    .lab-explorer {
      display: grid;
      grid-template-columns: minmax(220px, .8fr) minmax(0, 1.6fr);
      gap: 32px;
      align-items: start;
    }
    .lab-theories #labTheoryList { display: grid; gap: 8px; }
    .lab-theory-btn {
      display: block;
      width: 100%;
      text-align: left;
      padding: 12px 14px;
      border: 1px solid var(--line);
      border-radius: 12px;
      background: var(--panel-2);
      color: var(--ink);
      cursor: pointer;
    }
    .lab-theory-btn strong { display: block; font-size: 15px; }
    .lab-theory-btn span { font-size: 12px; color: var(--dim); }
    .lab-theory-btn:hover, .lab-theory-btn:focus-visible { border-color: var(--cyan); }
    .lab-detail-wrap { min-width: 0; }
    .lab-detail-wrap h3 { margin: 6px 0 16px; font-size: 24px; }
    .lab-chip-row { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 18px; }
    .lab-claim-chip {
      font: 500 12px "IBM Plex Mono", monospace;
      padding: 6px 12px;
      border-radius: 999px;
      border: 1px solid var(--cyan);
      background: transparent;
      color: var(--cyan);
      cursor: pointer;
    }
    .lab-claim-chip.direct { background: var(--cyan); color: var(--black); font-weight: 600; }
    .lab-implied-wrap { display: inline-flex; align-items: center; gap: 6px; }
    .lab-implied-wrap small { color: var(--dim); font-size: 11px; }
    .lab-claim-text {
      border-left: 2px solid var(--line);
      padding: 4px 0 4px 14px;
      margin-bottom: 14px;
    }
    .lab-claim-text.direct { border-left-color: var(--cyan); }
    .lab-claim-text p { margin: 4px 0 0; color: #c3cac7; }
    .lab-claim-id {
      font: 500 11px "IBM Plex Mono", monospace;
      letter-spacing: .1em;
      text-transform: uppercase;
      color: var(--dim);
    }
    .lab-claim-title { font-size: 22px; line-height: 1.35; font-weight: 500; }
    .lab-plain { color: var(--muted); margin: 0 0 24px; }
    .lab-anti-note { color: var(--muted); font-size: 14px; margin: -12px 0 20px; }
    .lab-claim-cols {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      margin-bottom: 8px;
    }
    .lab-empty { color: var(--dim); font-size: 14px; }
    .lab-caveat { color: var(--dim); font-size: 13px; border-left: 2px solid var(--line); padding-left: 10px; margin: 8px 0 20px; }
    .lab-theory-chip {
      padding: 8px 14px;
      border-radius: 999px;
      border: 1px solid var(--line);
      background: var(--panel-2);
      color: var(--ink);
      cursor: pointer;
      font-size: 13px;
    }
    .lab-theory-chip.direct { border-color: var(--cyan); color: var(--cyan); }
    .lab-quiz h3 { margin: 8px 0 12px; font-size: 26px; }
    /* Keep the Agree/Disagree buttons in a steadier spot: claim texts vary
       in length, so reserve room for ~3 lines of question text. */
    .lab-quiz #labQText { min-height: 3.2em; }
    .lab-quiz .lab-plain { max-width: 640px; }
    .lab-quiz-grid {
      display: grid;
      grid-template-columns: minmax(0, 1.6fr) minmax(220px, .7fr);
      gap: 32px;
      align-items: start;
    }
    .lab-rail {
      border: 1px solid var(--line);
      border-radius: 14px;
      padding: 18px;
      background: var(--panel-2);
    }
    .lab-score-row { margin-bottom: 14px; }
    .lab-score-row:last-child { margin-bottom: 0; }
    .lab-score-top {
      display: flex;
      justify-content: space-between;
      gap: 10px;
      font-size: 13px;
      margin-bottom: 6px;
    }
    .lab-score-top span { color: var(--cyan); font-family: "IBM Plex Mono", monospace; font-size: 12px; }
    .lab-score-bar { height: 4px; border-radius: 2px; background: #253031; overflow: hidden; }
    .lab-score-bar span { display: block; height: 100%; background: var(--cyan); }
    .lab-score-row small { color: var(--coral); font-size: 11px; }
    .lab-result-row {
      display: flex;
      gap: 16px;
      align-items: baseline;
      padding: 14px 0;
      border-bottom: 1px solid var(--line);
    }
    .lab-result-row.top strong { color: var(--cyan); }
    .lab-result-rank {
      font: 500 13px "IBM Plex Mono", monospace;
      color: var(--dim);
      min-width: 24px;
    }
    .vh {
      position: absolute;
      width: 1px;
      height: 1px;
      overflow: hidden;
      clip: rect(0 0 0 0);
      clip-path: inset(50%);
      white-space: nowrap;
    }
    .lab-result-row p { margin: 4px 0 0; color: var(--muted); font-size: 14px; }
    #labQuizRestart { margin-top: 24px; }
    .dag-key {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 18px;
      margin-bottom: 24px;
      color: var(--muted);
      font-size: 13px;
    }
    .dag-key p { margin: 0; }
    .dag-root-key { display: inline-flex; align-items: center; gap: 8px; white-space: nowrap; }
    .dag-root-key::before { content: ""; width: 11px; height: 11px; border: 2px solid var(--coral); }
    .claim-graph {
      display: grid;
      grid-template-columns: 1fr;
      gap: 20px;
      align-items: start;
      margin-bottom: 30px;
    }
    .dag-scroll {
      overflow-x: auto;
      border-top: 1px solid var(--line);
      background: #0f1718;
      /* The "scroll sideways to see all" label needs a visible affordance:
         an always-visible slim scrollbar, not just hover-only chrome. */
      scrollbar-width: thin;
      scrollbar-color: #7aa39f rgba(255, 255, 255, 0.08);
    }
    .dag-scroll::-webkit-scrollbar { height: 10px; }
    .dag-scroll::-webkit-scrollbar-track { background: rgba(255, 255, 255, 0.06); }
    .dag-scroll::-webkit-scrollbar-thumb { background: #7aa39f; border-radius: 5px; }
    .dag-component {
      position: relative;
      min-width: 100%;
    }
    .dag-component svg {
      position: absolute;
      inset: 0;
      width: 100%;
      height: 100%;
      pointer-events: none;
      overflow: visible;
    }
    .dag-edge { fill: none; stroke: #49615f; stroke-width: 1.35; }
    .dag-node {
      position: absolute;
      z-index: 1;
      width: 172px;
      min-height: 58px;
      padding: 8px 9px;
      border: 1px solid #40504f;
      border-radius: 5px 12px 5px 12px;
      background: var(--panel-2);
      color: var(--ink);
      text-align: left;
      cursor: pointer;
      line-height: 1.2;
      transform: translateX(-50%);
    }
    .dag-node:hover, .dag-node:focus-visible, .dag-node.selected { border-color: var(--cyan); background: #192627; }
    .dag-node.root { border-color: var(--coral); }
    .dag-node-id { display: block; margin-bottom: 4px; color: var(--cyan); font: 500 10px/1 "IBM Plex Mono", monospace; text-transform: uppercase; }
    .dag-node-label { display: block; font-size: 12px; font-weight: 600; }
    .dag-node[data-plain]:hover::after, .dag-node[data-plain]:focus-visible::after {
      content: attr(data-plain);
      position: absolute; left: 50%; bottom: calc(100% + 8px); transform: translateX(-50%);
      width: max-content; max-width: 260px;
      background: var(--panel-2); color: var(--ink); border: 1px solid var(--cyan);
      border-radius: 8px; padding: 8px 10px; font-size: 12px; font-weight: 400;
      line-height: 1.35; z-index: 60; pointer-events: none; text-align: left;
      box-shadow: 0 8px 24px rgba(0,0,0,.45);
    }
    .claim-detail-panel { padding-top: 24px; border-top: 1px solid var(--line); }
    .claim-detail-panel:empty { display: none; }
    .claim-detail-panel .lab-claim-title { max-width: 780px; }
    .claim-detail-groups { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-top: 24px; }
    .claim-detail-groups .lab-chip-row { margin-bottom: 0; }
    .lab-theory-btn.active { border-color: var(--cyan); background: #192627; }
    .lab-search {
      width: 100%;
      margin: 10px 0 12px;
      padding: 9px 12px;
      border: 1px solid var(--line);
      border-radius: 8px;
      background: var(--panel-2);
      color: var(--ink);
      font: inherit;
      font-size: 14px;
    }
    .lab-search::placeholder { color: var(--muted); }
    .lab-search:focus { outline: none; border-color: var(--cyan); }
    @media (max-width: 860px) {
      .lab-explorer, .lab-quiz-grid, .lab-claim-cols, .claim-detail-groups { grid-template-columns: 1fr; }
    }
    @media (max-width: 560px) {
      .claims-lab { margin-top: 48px; padding-top: 36px; }
      .lab-head { align-items: stretch; }
      .lab-tabs { display: grid; grid-template-columns: 1fr; }
      .lab-tab { padding-inline: 12px; }
      .lab-pane { padding: 20px 16px; }
      .lab-explorer { gap: 24px; }
      .lab-claim-title { font-size: 20px; }
      .lab-score-top { align-items: flex-start; }
      .claim-graph { gap: 14px; }
      .dag-key { align-items: flex-start; flex-direction: column; gap: 8px; }
    }
      /* Quiz-first landing (round 1 restructure) */
    .quiz-section { padding: 36px 0 8px; }
    .lab-theory-group {
      margin: 18px 0 8px;
      font: 500 11px/1.25 "IBM Plex Mono", monospace;
      letter-spacing: .14em;
      text-transform: uppercase;
      color: var(--dim);
    }
    .lab-theory-pending { opacity: .72; }
    .lab-claim-plain { color: var(--muted); font-size: 14px; }
    .lab-settled-by { color: var(--dim); font-size: 13px; margin: -14px 0 20px; }
    /* The leading marker reflects the last answer's direction: a ✓ after
       Agree used to appear after Disagree too, implying affirmation. */
    .lab-settled-by.dir-yes:not(:empty)::before { content: "✓ "; color: var(--cyan); }
    .lab-settled-by.dir-no:not(:empty)::before { content: "✗ "; color: var(--coral); }
    .lab-settled-by:not(.dir-yes):not(.dir-no):not(:empty)::before { content: "• "; color: var(--dim); }
    /* Per-bullet disposition marks in the settled list: ✓ settled-as-agreed,
       ✗ settled-as-ruled-out, so "settled" is never ambiguous. */
    .settled-mark { display: inline-block; width: 1.25em; font-weight: 700; }
    .settled-mark-yes { color: var(--cyan); }
    .settled-mark-no { color: var(--coral); }
    .settled-anti-note { color: var(--cyan); font-weight: 600; }
    /* ↔ mark on graph nodes that have a direct opposite claim. */
    .dag-anti-mark { color: var(--cyan); font-weight: 700; margin-left: 6px; }
    .dag-anti-key { display: inline-flex; align-items: center; gap: 8px; white-space: nowrap; color: var(--cyan); font-weight: 700; }
    .lab-tension { color: #f2d98c; font-size: 13px; margin: -14px 0 20px; border-left: 2px solid #8a6d1f; padding-left: 10px; }
    .lab-scores-more { color: var(--dim); font-size: 13px; margin: 8px 0 0; text-align: left; cursor: pointer; }
    .lab-continue-note { color: var(--dim); font-size: 14px; margin: 0 0 16px; }
    .update-banner { background: #3a2f10; border: 1px solid #8a6d1f; color: #f2d98c; border-radius: 10px; padding: 10px 14px; margin: 0 0 16px; font-size: 14px; }
    .update-banner .text-btn { color: #ffe9a8; text-decoration: underline; font-size: 14px; }
    .lab-score-blurb, .lab-result-blurb { color: var(--dim); font-size: 13px; margin: 2px 0 6px; }

    /* Build 37: simpler verdict buttons, progress pill, explain panel, load-more */
    .question-head-row {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 12px;
      margin-bottom: 18px;
      position: sticky;
      top: 0;
      z-index: 40;
      padding: 10px 2px;
      background: color-mix(in srgb, var(--panel) 92%, transparent);
    }
    .progress-pill {
      font: 500 12px/1.4 "IBM Plex Mono", monospace;
      color: var(--cyan);
      border: 1px solid #2c3f3e;
      border-radius: 999px;
      background: #101819;
      padding: 8px 14px;
      white-space: nowrap;
    }
    .lab-quiz .answers { grid-template-columns: 1fr 1fr; }
    .lab-quiz .answer-btn {
      min-height: 84px;
      padding: 18px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      text-align: center;
      font-size: 19px;
    }
    .lab-quiz .answer-btn .verdict { font-size: 24px; line-height: 1; }
    .lab-quiz .answer-btn.agree { border-color: #2f6b4e; }
    .lab-quiz .answer-btn.agree .verdict { color: #57d98a; }
    .lab-quiz .answer-btn.agree:hover { border-color: #57d98a; background: #132620; }
    .lab-quiz .answer-btn.disagree { border-color: #74403d; }
    .lab-quiz .answer-btn.disagree .verdict { color: #f08080; }
    .lab-quiz .answer-btn.disagree:hover { border-color: #f08080; background: #281414; }
    .pick-group { margin-top: 8px; }
    .pick-prompt { margin-bottom: 12px; }
    .pick-options { display: grid; gap: 12px; }
    .pick-option {
      display: block;
      width: 100%;
      text-align: left;
      padding: 16px 18px;
      border: 1px solid var(--border);
      border-radius: 12px;
      background: var(--card);
      color: var(--text);
      cursor: pointer;
      font-size: 17px;
      line-height: 1.45;
    }
    .pick-option:hover { border-color: var(--cyan); background: #192627; }
    .pick-option .pick-plain { display: block; margin-top: 6px; font-size: 14px; color: var(--muted); }
    /* Non-exclusive (method) card note: a stance that combines with the others. */
    .pick-option .pick-note { display: block; margin-top: 8px; font-size: 13px; color: var(--cyan); }
    /* "What does this mean?" jargon definitions under a question. */
    .jargon-term { display: grid; grid-template-columns: minmax(88px, auto) 1fr; gap: 4px 12px; margin: 8px 0; font-size: 14px; }
    .jargon-term dt { font-weight: 600; color: var(--cyan); }
    .jargon-term dd { margin: 0; color: var(--muted); }
    /* Zero-alignment rail rows: dimmed so a ruled-out theory never reads as a recommendation. */
    .lab-score-zero { opacity: .55; }
    .rail-legend { color: var(--dim); margin-top: 6px; }
    .pick-actions { margin-top: 14px; display: flex; justify-content: center; }
    .skip-actions { display: flex; gap: 16px; align-items: center; }
    .explain-panel {
      margin-top: 20px;
      padding: 22px;
      border: 1px solid var(--cyan);
      border-radius: 14px;
      background: #101c1d;
    }
    .explain-panel .micro { margin-bottom: 6px; }
    .explain-panel h4 { margin: 0 0 10px; font-size: 19px; line-height: 1.4; font-weight: 600; }
    .explain-panel .lab-plain { margin-bottom: 16px; }
    .explain-panel .explainer-points { margin: 0 0 16px; }
    .explain-note { color: var(--dim); font-size: 13px; margin: 4px 0 0; }
    .explain-actions { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; margin-top: 18px; }
    .explain-actions .primary { padding: 12px 18px; }
    .chip-more { margin: 2px 0 0; }
    .lab-list-more { margin: 6px 0 0; }
    .result-show-all-wrap { margin-top: 12px; }

    /* Build 38: collapsed settled trace, stable tension slot, rail deltas, detail flash, claim search */
    .lab-settled-by .settled-details { margin: 8px 0 0; padding-left: 20px; color: var(--dim); font-size: 12.5px; }
    .lab-settled-by .settled-details li { margin-bottom: 4px; }
    /* Build 40: the "details" expander is a real affordance now — pill button
       with a chevron and a thumb-sized tap target, still secondary to the
       main answer buttons. */
    .lab-settled-by .settled-more-btn, .lab-tension .settled-more-btn {
      display: inline-block; padding: 7px 12px; border: 1px solid var(--dim);
      border-radius: 999px; font-size: 13px; line-height: 1.2; min-height: 32px;
    }
    .lab-settled-by .settled-more-btn:hover, .lab-tension .settled-more-btn:hover {
      color: var(--ink); border-color: var(--ink);
    }
    .lab-tension { min-height: 38px; }
    .lab-tension.tension-empty { visibility: hidden; }
    .tension-details { margin: 6px 0 0; }
    .lab-score-top .rank-delta { font: 600 10px/1 "IBM Plex Mono", monospace; padding: 3px 7px; border-radius: 999px; vertical-align: 1px; white-space: nowrap; }
    .lab-score-top .rank-delta.up { color: #57d98a; background: #132620; }
    .lab-score-top .rank-delta.down { color: #f08080; background: #281414; }
    #labDetail.detail-flash { animation: detailFlash 1.6s ease-out; border-radius: 12px; }
    @keyframes detailFlash { 0% { box-shadow: 0 0 0 3px var(--cyan); } 100% { box-shadow: 0 0 0 0 transparent; } }
    .dag-search-row { display: flex; align-items: center; gap: 14px; margin-top: 12px; flex-wrap: wrap; }
    .dag-search-row .lab-search { max-width: 300px; margin: 0; }
    .dag-node { transition: opacity .18s ease; }
    .dag-node.dimmed { opacity: .18; }
    .dag-node.dimmed-anti { opacity: .18; }