:root {
  --demo-blue: #0b5ee8;
  --demo-blue-hover: #084cc0;
  --demo-blue-soft: #edf4ff;
  --demo-navy: #061d50;
  --demo-navy-2: #0a2d70;
  --demo-text: #2d3f61;
  --demo-muted: #6f7f9c;
  --demo-line: #dce5f2;
  --demo-line-strong: #c4d0e2;
  --demo-green: #13865f;
  --demo-green-soft: #eaf8f2;
  --demo-gold: #f2b84b;
  --demo-paper: #ffffff;
  --demo-wash: #f7faff;
  --demo-font: "Microsoft YaHei UI", "PingFang SC", "HarmonyOS Sans SC", "Noto Sans CJK SC", "Segoe UI", Arial, sans-serif;
}

* { box-sizing: border-box; }

html {
  background: var(--demo-paper);
  color-scheme: light;
}

body {
  min-width: 300px;
  min-height: 100vh;
  margin: 0;
  padding: 82px 0 94px;
  overflow-x: hidden;
  background: var(--demo-paper);
  color: var(--demo-navy);
  font-family: var(--demo-font);
  -webkit-font-smoothing: antialiased;
}

button,
textarea,
input { font: inherit; }

button,
a { -webkit-tap-highlight-color: transparent; }

button:focus-visible,
a:focus-visible,
textarea:focus-visible,
input:focus-visible {
  outline: 3px solid rgba(55, 142, 255, 0.32);
  outline-offset: 3px;
}

.demo-topbar {
  position: fixed;
  inset: 0 0 auto;
  z-index: 1000;
  display: grid;
  grid-template-columns: minmax(280px, 1fr) auto minmax(300px, 1fr);
  align-items: stretch;
  height: 82px;
  padding: 0 clamp(18px, 2.5vw, 48px);
  border-bottom: 1px solid var(--demo-line);
  background: #fff;
  color: var(--demo-navy);
  box-shadow: 0 4px 18px rgba(25, 62, 117, 0.05);
}

.demo-brand {
  display: inline-flex;
  align-items: center;
  gap: 13px;
  min-width: 0;
  padding-right: 18px;
  color: var(--demo-navy);
  text-decoration: none;
  font-size: clamp(13px, 1.02vw, 17px);
  font-weight: 800;
  letter-spacing: 0.01em;
}

.demo-brand > span:last-child {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.demo-brand-mark {
  display: grid;
  flex: 0 0 40px;
  width: 40px;
  height: 48px;
  place-items: center;
  color: var(--demo-blue);
  font-family: Cambria, Georgia, serif;
  font-size: 36px;
  font-weight: 500;
}

.demo-primary-nav {
  display: flex;
  align-items: stretch;
  height: 82px;
}

.demo-primary-nav a {
  display: grid;
  min-width: 92px;
  padding: 0 clamp(14px, 1.35vw, 24px);
  place-items: center;
  color: var(--demo-text);
  text-decoration: none;
  font-size: clamp(12px, 0.9vw, 15px);
  font-weight: 800;
  white-space: nowrap;
}

.demo-primary-nav a:hover,
.demo-primary-nav a.is-current {
  background: var(--demo-blue-soft);
  color: var(--demo-blue);
}

.demo-primary-nav a.is-current { box-shadow: inset 0 -3px 0 var(--demo-blue); }

.demo-top-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
  min-width: 0;
}

.demo-language { display: flex; align-items: center; }

.demo-language .ws-language-switch {
  min-height: 38px;
  border-color: var(--demo-line-strong);
  background: #fff;
  box-shadow: none;
  color: var(--demo-navy);
}

.demo-language .ws-language-switch__button,
.demo-language .ws-language-switch__option { color: var(--demo-navy); }

.demo-exit,
.top-reviewer-entry {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  border-radius: 7px;
  cursor: pointer;
  font-size: 12px;
  font-weight: 900;
  white-space: nowrap;
}

.demo-exit {
  gap: 8px;
  padding: 0 14px;
  border: 1px solid var(--demo-line-strong);
  color: var(--demo-navy);
  text-decoration: none;
}

.demo-exit:hover { border-color: var(--demo-blue); background: var(--demo-blue-soft); color: var(--demo-blue); }

.top-reviewer-entry {
  min-width: 92px;
  padding: 0 16px;
  border: 1px solid var(--demo-line-strong);
  background: #fff;
  color: var(--demo-navy);
}

.top-reviewer-entry:hover { border-color: var(--demo-blue); background: var(--demo-blue-soft); color: var(--demo-blue); }

.demo-shell {
  width: min(1840px, calc(100% - clamp(28px, 4vw, 78px)));
  margin: 0 auto;
}

.demo-page-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 112px;
  padding: 22px 0 18px;
}

.demo-page-heading h1 {
  margin: 0;
  color: var(--demo-navy);
  font-size: clamp(29px, 2.6vw, 43px);
  font-weight: 900;
  letter-spacing: -0.045em;
}

.demo-presentation {
  display: grid;
  grid-template-columns: 112px minmax(0, 1fr);
  gap: clamp(18px, 2vw, 34px);
  align-items: start;
  padding: 26px 0 34px;
}

.demo-progress {
  position: sticky;
  top: 104px;
  display: grid;
  justify-items: center;
  min-width: 0;
  padding-top: 8px;
}

.demo-progress > div:first-child {
  display: grid;
  justify-items: center;
  gap: 8px;
  width: 100%;
  margin-bottom: 14px;
  text-align: center;
}

.demo-progress strong,
.demo-controls strong {
  color: var(--demo-blue);
  font-size: 15px;
  font-variant-numeric: tabular-nums;
}

.demo-progress #stepName,
.demo-controls p span {
  color: var(--demo-muted);
  font-size: 10px;
  font-weight: 800;
  line-height: 1.4;
}

.step-dots {
  position: relative;
  display: grid;
  gap: 25px;
  justify-items: center;
  width: 100%;
  margin: 0;
  padding: 0;
  list-style: none;
}

.step-dots::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: 24px;
  bottom: 24px;
  left: 50%;
  width: 2px;
  background: var(--demo-line);
  transform: translateX(-50%);
}

.step-dots button {
  display: grid;
  width: 48px;
  height: 48px;
  padding: 0;
  place-items: center;
  border: 1px solid var(--demo-line-strong);
  border-radius: 50%;
  background: #fff;
  color: var(--demo-muted);
  cursor: pointer;
  font-size: 13px;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
}

.step-dots button:hover,
.step-dots button[aria-current="step"] {
  border-color: var(--demo-blue);
  background: var(--demo-blue);
  color: #fff;
  box-shadow: 0 0 0 5px #fff, 0 0 0 6px #b9d2fb;
}

.progress-line {
  width: 58px;
  height: 3px;
  margin-top: 18px;
  overflow: hidden;
  border-radius: 99px;
  background: var(--demo-line);
}

.progress-line i {
  display: block;
  width: 20%;
  height: 100%;
  border-radius: inherit;
  background: var(--demo-blue);
  transition: width 260ms ease;
}

.demo-stage {
  min-width: 0;
  overflow: hidden;
  border: 0;
  border-radius: 0;
  background: #fff;
  box-shadow: none;
}

.demo-step {
  min-width: 0;
  min-height: min(660px, calc(100vh - 240px));
}

.demo-step[hidden] { display: none !important; }

.step-intro {
  position: relative;
  display: grid;
  grid-template-columns: 68px minmax(0, 1fr);
  grid-template-rows: auto auto auto;
  column-gap: 18px;
  align-items: center;
  min-height: 122px;
  padding: 20px clamp(20px, 2.2vw, 36px);
  border-top: 1px solid var(--demo-line);
  border-bottom: 1px solid var(--demo-line);
}

.step-number {
  display: grid;
  grid-row: 1 / 4;
  width: 58px;
  height: 58px;
  place-items: center;
  border-radius: 50%;
  background: var(--demo-blue);
  color: #fff;
  box-shadow: 0 0 0 5px var(--demo-blue-soft);
  font-size: 18px;
  font-weight: 900;
  font-variant-numeric: tabular-nums;
}

.step-kicker,
.content-label,
.case-heading > div > span,
.model-heading > div > span,
.evidence-heading > span,
.prompt-box > span {
  margin: 0;
  color: var(--demo-blue);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

.step-intro h1 {
  margin: 3px 0 2px;
  color: var(--demo-navy);
  font-size: clamp(23px, 1.9vw, 33px);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.025em;
}

.step-lead {
  display: none;
}

.step-workspace { min-width: 0; background: #fff; }

.ebook-workspace {
  display: grid;
  grid-template-columns: clamp(190px, 16vw, 260px) minmax(0, 1fr);
  min-height: 570px;
}

.chapter-strip {
  display: grid;
  grid-auto-rows: minmax(42px, auto);
  align-content: start;
  min-width: 0;
  border-right: 1px solid var(--demo-line);
  background: #fbfdff;
}

.chapter-chip {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 8px;
  align-items: center;
  min-width: 0;
  min-height: 42px;
  padding: 7px 12px;
  border: 0;
  border-bottom: 1px solid #e9eef6;
  background: transparent;
  color: var(--demo-text);
  text-align: left;
  cursor: pointer;
  font-size: 10px;
  line-height: 1.25;
}

.chapter-chip b { color: var(--demo-blue); font-size: 11px; font-variant-numeric: tabular-nums; }
.chapter-chip span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.chapter-chip:hover,
.chapter-chip.is-current {
  box-shadow: inset 4px 0 0 var(--demo-blue);
  background: #eaf2ff;
  color: var(--demo-blue);
  font-weight: 800;
}

.textbook-page {
  display: grid;
  grid-template-columns: minmax(300px, 0.39fr) minmax(420px, 0.61fr);
  min-width: 0;
}

.textbook-copy {
  min-width: 0;
  padding: clamp(24px, 2.4vw, 40px);
  border-right: 1px solid var(--demo-line);
}

.textbook-copy h2 {
  margin: 10px 0 15px;
  color: var(--demo-navy);
  font-size: clamp(22px, 1.7vw, 30px);
  line-height: 1.25;
}

.textbook-copy > p {
  margin: 0;
  color: var(--demo-text);
  font-size: 12px;
  line-height: 1.78;
}

.formula {
  margin: 20px 0;
  padding: 12px 15px;
  border-left: 3px solid var(--demo-blue);
  background: var(--demo-wash);
  color: var(--demo-navy);
  font-family: Cambria, Georgia, serif;
  font-size: clamp(19px, 1.55vw, 27px);
  font-style: italic;
}

.parameter-controls { display: grid; gap: 14px; }

.parameter-controls label,
.weight-controls label {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 7px 12px;
  align-items: center;
  color: var(--demo-text);
  font-size: 11px;
  font-weight: 800;
}

.parameter-controls label span { display: flex; gap: 7px; align-items: center; }
.parameter-controls i { color: var(--demo-blue); font-family: Georgia, serif; font-size: 16px; }
.parameter-controls em { font-style: normal; }
.parameter-controls output,
.weight-controls output { color: var(--demo-blue); font-variant-numeric: tabular-nums; }

input[type="range"] {
  grid-column: 1 / -1;
  width: 100%;
  accent-color: var(--demo-blue);
  cursor: pointer;
}

.graph-stage {
  display: grid;
  min-width: 0;
  min-height: 500px;
  padding: clamp(16px, 1.7vw, 28px);
  place-items: center;
  background: #fff;
}

.graph-stage canvas {
  display: block;
  width: 100%;
  height: auto;
  max-height: 510px;
  border: 1px solid var(--demo-line);
  background: #fff;
}

.competency-workspace,
.question-workspace,
.modeling-workspace,
.evidence-workspace { padding: clamp(24px, 2.6vw, 42px); }

.case-heading,
.model-heading,
.evidence-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 18px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--demo-line);
}

.case-heading h2,
.model-heading h2 {
  margin: 7px 0 0;
  color: var(--demo-navy);
  font-size: clamp(23px, 2vw, 34px);
  line-height: 1.25;
}

.case-pill {
  flex: 0 0 auto;
  padding: 6px 10px;
  border-radius: 999px;
  background: var(--demo-green-soft);
  color: var(--demo-green);
  font-size: 9px;
  font-weight: 900;
  letter-spacing: 0.08em;
}

.competency-chain {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  margin-top: 26px;
}

.layer-button {
  position: relative;
  display: grid;
  min-width: 0;
  min-height: 94px;
  padding: 13px 8px;
  place-items: center;
  border: 0;
  border-top: 2px solid var(--demo-line-strong);
  background: #fff;
  color: var(--demo-muted);
  text-align: center;
  cursor: pointer;
}

.layer-button:not(:last-child)::after {
  content: "→";
  position: absolute;
  top: -13px;
  right: -8px;
  z-index: 2;
  padding: 0 4px;
  background: #fff;
  color: var(--demo-line-strong);
}

.layer-button b { color: var(--demo-blue); font-size: 12px; }
.layer-button span { font-size: 11px; font-weight: 800; line-height: 1.4; }

.layer-button:hover,
.layer-button.is-active {
  border-color: var(--demo-blue);
  background: var(--demo-blue-soft);
  color: var(--demo-navy);
}

.layer-detail {
  min-height: 185px;
  margin-top: 16px;
  padding: 24px;
  border-top: 1px solid var(--demo-line);
  background: var(--demo-wash);
}

.layer-detail h3 { margin: 0 0 14px; font-size: 17px; }
.layer-detail ul { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px 22px; margin: 0; padding: 0; list-style: none; }
.layer-detail li { position: relative; padding-left: 16px; color: var(--demo-text); font-size: 12px; line-height: 1.6; }
.layer-detail li::before { content: ""; position: absolute; top: 0.62em; left: 0; width: 6px; height: 6px; border-radius: 50%; background: var(--demo-blue); }

.chain-thesis {
  margin: 20px 0 0;
  padding: 15px 18px;
  border-left: 3px solid var(--demo-green);
  background: var(--demo-green-soft);
  color: #155c47;
  font-size: 12px;
  font-weight: 800;
  line-height: 1.6;
}

.prompt-box { display: grid; gap: 10px; }

.prompt-box textarea {
  width: 100%;
  min-height: 104px;
  resize: vertical;
  padding: 15px 18px;
  border: 1px solid var(--demo-line-strong);
  border-radius: 6px;
  background: #fff;
  color: var(--demo-navy);
  font-size: 14px;
  line-height: 1.6;
}

.question-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 0 20px;
  border-bottom: 1px solid var(--demo-line);
}

.primary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  min-height: 42px;
  padding: 0 20px;
  border: 1px solid var(--demo-blue);
  border-radius: 6px;
  background: var(--demo-blue);
  color: #fff;
  cursor: pointer;
  font-size: 12px;
  font-weight: 900;
}

.primary-action:hover { background: var(--demo-blue-hover); }
.primary-action:disabled { cursor: wait; opacity: 0.68; }
.question-actions p { margin: 0; color: var(--demo-muted); font-size: 11px; }
.question-output { min-height: 310px; padding-top: 20px; }

.empty-output {
  display: grid;
  min-height: 280px;
  place-items: center;
  align-content: center;
  gap: 12px;
  color: var(--demo-muted);
  text-align: center;
}

.empty-output b { color: var(--demo-blue); font-size: 66px; opacity: 0.12; }

.result-label {
  display: inline-flex;
  margin-bottom: 14px;
  padding: 6px 10px;
  border-radius: 999px;
  background: var(--demo-green-soft);
  color: var(--demo-green);
  font-size: 9px;
  font-weight: 900;
  letter-spacing: 0.08em;
}

.result-label.is-sample { background: #fff5d9; color: #8b6111; }
.question-list { display: grid; gap: 12px; }
.question-card { padding: 18px 0 0; border-top: 1px solid var(--demo-line); }
.question-card:first-child { border-top: 0; padding-top: 0; }
.question-card h3 { margin: 0 0 10px; font-size: 16px; line-height: 1.5; }
.question-meta { display: flex; flex-wrap: wrap; gap: 7px; margin-bottom: 10px; }
.question-meta span { padding: 4px 8px; border-radius: 4px; background: var(--demo-wash); color: var(--demo-muted); font-size: 9px; font-weight: 800; }
.question-card dl { display: grid; grid-template-columns: 82px 1fr; gap: 6px 12px; margin: 0; font-size: 11.5px; line-height: 1.6; }
.question-card dt { color: var(--demo-muted); font-weight: 800; }
.question-card dd { margin: 0; color: var(--demo-text); }
.question-card dd:last-child { color: var(--demo-blue); font-weight: 900; }

.model-heading > p { display: grid; gap: 3px; margin: 0; text-align: right; }
.model-heading > p b { color: var(--demo-blue); font-size: 21px; }
.model-heading > p span { color: var(--demo-muted); font-size: 9px; }

.model-grid {
  display: grid;
  grid-template-columns: minmax(220px, 0.31fr) minmax(0, 0.69fr);
  gap: 32px;
  padding-top: 26px;
}

.weight-controls { display: grid; align-content: start; gap: 22px; }
.weight-controls > p { margin: 0; padding-top: 14px; border-top: 1px solid var(--demo-line); color: var(--demo-muted); font-size: 10px; line-height: 1.65; }
.ranking-stage { display: grid; align-content: start; gap: 0; border-top: 1px solid var(--demo-line); }

.rank-row {
  display: grid;
  grid-template-columns: 42px minmax(120px, 0.8fr) minmax(140px, 1.2fr) 54px;
  gap: 12px;
  align-items: center;
  min-height: 82px;
  padding: 12px 8px;
  border-bottom: 1px solid var(--demo-line);
  transition: background 180ms ease;
}

.rank-row.is-first { background: var(--demo-blue-soft); }
.rank-number { color: var(--demo-blue); font-size: 22px; }
.rank-name { display: grid; gap: 3px; }
.rank-name b { font-size: 13px; }
.rank-name span { color: var(--demo-muted); font-size: 9px; }
.rank-track { height: 8px; overflow: hidden; border-radius: 99px; background: var(--demo-line); }
.rank-track i { display: block; height: 100%; border-radius: inherit; background: var(--demo-blue); transition: width 220ms ease; }
.rank-score { color: var(--demo-blue); text-align: right; font-size: 15px; font-variant-numeric: tabular-nums; }

.evidence-workspace { display: grid; gap: 26px; }
.evidence-heading { align-items: center; padding-bottom: 12px; }
.evidence-heading p { margin: 0; color: var(--demo-muted); font-size: 9px; text-align: right; }
.metric-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-bottom: 1px solid var(--demo-line); }
.metric-grid.five { grid-template-columns: repeat(5, minmax(0, 1fr)); }
.metric-grid > div { min-width: 0; padding: 20px 14px 22px; border-right: 1px solid var(--demo-line); }
.metric-grid > div:first-child { padding-left: 0; }
.metric-grid > div:last-child { border-right: 0; }
.metric-grid strong { display: block; color: var(--demo-blue); font-size: clamp(27px, 2.4vw, 40px); font-variant-numeric: tabular-nums; }
.metric-grid span { display: block; margin-top: 5px; color: var(--demo-muted); font-size: 10px; line-height: 1.4; }

.evidence-links { display: flex; flex-wrap: wrap; gap: 9px; }
.evidence-links a { padding: 9px 13px; border: 1px solid var(--demo-line-strong); border-radius: 5px; color: var(--demo-navy); text-decoration: none; font-size: 11px; font-weight: 800; }
.evidence-links a:hover { border-color: var(--demo-blue); color: var(--demo-blue); }

.review-dialog[hidden] { display: none; }
.review-dialog { position: fixed; z-index: 1900; inset: 0; display: grid; place-items: center; padding: 20px; }
.review-dialog-backdrop { position: absolute; inset: 0; border: 0; background: rgba(6, 29, 80, 0.32); backdrop-filter: blur(6px); cursor: pointer; }
.review-dialog-panel { position: relative; width: min(680px, 100%); padding: clamp(28px, 4vw, 46px); border: 1px solid var(--demo-line); border-radius: 12px; background: #fff; box-shadow: 0 28px 80px rgba(6, 29, 80, 0.2); }
.review-label { color: var(--demo-blue); font-size: 10px; font-weight: 900; letter-spacing: 0.15em; }
.review-dialog-panel h2 { margin: 10px 0 24px; font-size: clamp(27px, 3.5vw, 39px); }
.review-dialog-close { position: absolute; top: 13px; right: 13px; width: 40px; height: 40px; border: 0; border-radius: 50%; background: var(--demo-wash); color: var(--demo-navy); cursor: pointer; font-size: 24px; }
.review-role-list { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.review-role-list > button { display: grid; grid-template-columns: 44px 1fr auto; gap: 13px; align-items: center; min-height: 108px; padding: 18px; border: 1px solid var(--demo-line); border-radius: 8px; background: #fff; color: var(--demo-navy); cursor: pointer; text-align: left; }
.review-role-list > button:hover { border-color: var(--demo-blue); background: var(--demo-blue-soft); }
.review-role-list strong { display: grid; width: 42px; height: 42px; place-items: center; border-radius: 50%; background: var(--demo-blue); color: #fff; }
.review-role-list span { display: grid; gap: 6px; }
.review-role-list b { font-size: 15px; }
.review-role-list small { color: var(--demo-muted); font-size: 10px; line-height: 1.5; }
.review-role-list i { color: var(--demo-blue); font-style: normal; font-size: 19px; }
#reviewDialogStatus { min-height: 18px; margin: 14px 0 0; color: var(--demo-blue); font-size: 11px; font-weight: 800; }
.review-dialog-open { overflow: hidden; }

.demo-controls {
  position: fixed;
  inset: auto 0 0;
  z-index: 900;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 142px 142px;
  gap: 12px;
  align-items: center;
  min-height: 76px;
  padding: 0 clamp(18px, 3vw, 58px);
  border-top: 1px solid var(--demo-line);
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 -8px 24px rgba(24, 57, 105, 0.04);
}

.demo-controls button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 44px;
  padding: 0 14px;
  border: 1px solid var(--demo-line-strong);
  border-radius: 6px;
  background: #fff;
  color: var(--demo-navy);
  cursor: pointer;
  font-size: 12px;
  font-weight: 900;
}

.demo-controls button:first-child { grid-column: 2; }
.demo-controls button.is-primary { grid-column: 3; border-color: var(--demo-blue); background: var(--demo-blue); color: #fff; }
.demo-controls button.is-primary:hover { background: var(--demo-blue-hover); }
.demo-controls button:disabled { cursor: not-allowed; opacity: 0.35; }
.demo-controls p { grid-column: 1; grid-row: 1; display: flex; align-items: baseline; gap: 10px; min-width: 0; margin: 0; }
.demo-controls p span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

@media (max-width: 1480px) {
  .demo-topbar { grid-template-columns: minmax(250px, 0.8fr) auto minmax(250px, 0.8fr); }
  .demo-primary-nav a { min-width: 78px; padding-inline: 12px; }
  .demo-brand { font-size: 12px; }
  .demo-exit { padding-inline: 10px; }
  .textbook-page { grid-template-columns: minmax(280px, 0.42fr) minmax(340px, 0.58fr); }
}

@media (max-width: 1120px) {
  body { padding-top: 72px; }
  .demo-topbar { grid-template-columns: minmax(0, 1fr) auto; height: 72px; }
  .demo-primary-nav { display: none; }
  .demo-presentation { grid-template-columns: 1fr; }
  .demo-progress {
    position: static;
    grid-template-columns: 155px minmax(0, 1fr);
    gap: 14px 20px;
    justify-items: stretch;
    padding: 0;
  }
  .demo-progress > div:first-child { justify-items: start; align-content: center; margin: 0; text-align: left; }
  .step-dots { grid-template-columns: repeat(5, 40px); gap: 14px; justify-content: end; width: auto; }
  .step-dots::before { top: 50%; right: 20px; bottom: auto; left: 20px; width: auto; height: 2px; transform: translateY(-50%); }
  .step-dots button { width: 40px; height: 40px; }
  .progress-line { grid-column: 1 / -1; width: 100%; margin: 0 0 2px; }
  /* Keep the evidence entry reachable before the metric grid on compact screens. */
  .evidence-links { order: -1; }
  .ebook-workspace { grid-template-columns: 1fr; }
  .chapter-strip {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    grid-auto-rows: auto;
    border-right: 0;
    border-bottom: 1px solid var(--demo-line);
  }
  .chapter-chip { border-right: 1px solid var(--demo-line); }
  .chapter-chip:nth-child(4n) { border-right: 0; }
  .textbook-page { grid-template-columns: minmax(280px, 0.42fr) minmax(340px, 0.58fr); }
}

@media (max-width: 780px) {
  body { padding-bottom: 80px; }
  .demo-topbar { padding-inline: 14px; }
  .demo-brand > span:last-child { max-width: 38vw; font-size: 11px; line-height: 1.2; white-space: normal; }
  .demo-brand-mark { flex-basis: 34px; width: 34px; font-size: 30px; }
  .demo-language .ws-language-switch { min-height: 34px; }
  .demo-exit span:first-child { display: none; }
  .demo-exit { min-width: 36px; padding: 0 10px; }
  .top-reviewer-entry { min-width: 78px; padding-inline: 10px; font-size: 11px; }
  .demo-shell { width: min(100% - 24px, 740px); }
  .demo-page-heading { min-height: 96px; }
  .demo-page-heading h1 { font-size: 29px; }
  .demo-presentation { padding-top: 20px; }
  .demo-progress { grid-template-columns: 1fr; }
  .demo-progress > div:first-child { display: flex; align-items: baseline; gap: 10px; }
  .step-dots { grid-template-columns: repeat(5, 38px); justify-content: space-between; }
  .step-dots button { width: 38px; height: 38px; }
  .step-intro { grid-template-columns: 52px minmax(0, 1fr); column-gap: 14px; padding: 18px; }
  .step-number { width: 46px; height: 46px; font-size: 15px; }
  .step-intro h1 { font-size: 23px; }
  .step-lead { font-size: 11px; }
  .chapter-strip { grid-template-columns: repeat(2, minmax(0, 1fr)); max-height: 224px; overflow-y: auto; }
  .chapter-chip:nth-child(4n) { border-right: 1px solid var(--demo-line); }
  .chapter-chip:nth-child(2n) { border-right: 0; }
  .textbook-page,
  .model-grid { grid-template-columns: 1fr; }
  .textbook-copy { border-right: 0; border-bottom: 1px solid var(--demo-line); }
  .graph-stage { min-height: 360px; }
  .competency-chain { grid-template-columns: 1fr; }
  .layer-button { grid-template-columns: 36px 1fr; min-height: 48px; place-items: center start; border-top: 0; border-left: 2px solid var(--demo-line-strong); text-align: left; }
  .layer-button:not(:last-child)::after { content: "↓"; top: auto; right: auto; bottom: -10px; left: 14px; }
  .layer-detail ul { grid-template-columns: 1fr; }
  .metric-grid,
  .metric-grid.five { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .metric-grid > div { border-bottom: 1px solid var(--demo-line); }
  .metric-grid > div:nth-child(2n) { border-right: 0; }
  .metric-grid > div:first-child { padding-left: 14px; }
  .demo-controls { grid-template-columns: minmax(0, 1fr) 112px 112px; padding-inline: 14px; }
}

@media (max-width: 520px) {
  body { padding-top: 64px; padding-bottom: 70px; }
  .demo-topbar { height: 64px; }
  .demo-brand { gap: 6px; padding-right: 4px; }
  .demo-brand-mark { flex-basis: 30px; width: 30px; font-size: 27px; }
  .demo-brand > span:last-child { max-width: 76px; font-size: 9px; }
  .demo-top-actions { gap: 4px; }
  .demo-language .ws-language-switch__button { padding-inline: 6px; }
  .demo-exit { display: none; }
  .top-reviewer-entry { min-width: 68px; min-height: 34px; padding-inline: 8px; font-size: 10px; }
  .demo-page-heading { display: grid; gap: 14px; padding: 20px 0 16px; }
  .demo-page-heading h1 { font-size: 27px; }
  .demo-presentation { gap: 15px; padding-top: 16px; }
  .demo-progress > div:first-child { justify-content: space-between; }
  .step-dots { grid-template-columns: repeat(5, 34px); gap: 0; }
  .step-dots button { width: 34px; height: 34px; font-size: 10px; }
  .demo-stage { border-radius: 8px; }
  .step-intro { grid-template-columns: 42px minmax(0, 1fr); column-gap: 11px; padding: 15px 13px; }
  .step-number { width: 38px; height: 38px; box-shadow: 0 0 0 3px var(--demo-blue-soft); font-size: 12px; }
  .step-kicker { font-size: 8px; }
  .step-intro h1 { margin-top: 2px; font-size: 19px; }
  .chapter-chip { grid-template-columns: 24px minmax(0, 1fr); padding-inline: 9px; font-size: 9px; }
  .textbook-copy,
  .competency-workspace,
  .question-workspace,
  .modeling-workspace,
  .evidence-workspace { padding: 20px 16px; }
  .graph-stage { min-height: 285px; padding: 10px; }
  .case-heading,
  .model-heading,
  .evidence-heading { display: grid; align-items: start; }
  .case-pill { justify-self: start; }
  .model-heading > p,
  .evidence-heading p { text-align: left; }
  .question-actions { align-items: flex-start; flex-direction: column; }
  .question-card dl { grid-template-columns: 1fr; }
  .question-card dd { margin-bottom: 6px; }
  .rank-row { grid-template-columns: 32px minmax(90px, 1fr) 42px; }
  .rank-track { grid-column: 2 / -1; }
  .metric-grid,
  .metric-grid.five { grid-template-columns: 1fr 1fr; }
  .evidence-heading p { word-break: break-word; }
  .review-role-list { grid-template-columns: 1fr; }
  .review-dialog-panel { padding: 32px 16px 20px; }
  .demo-controls { min-height: 62px; grid-template-columns: minmax(0, 1fr) 88px 88px; gap: 7px; padding-inline: 10px; }
  .demo-controls p span { display: none; }
  .demo-controls button { min-height: 38px; padding-inline: 7px; font-size: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.001ms !important; }
}

@media print {
  body { padding: 0; }
  .demo-topbar,
  .demo-controls,
  .demo-progress,
  .demo-page-heading { display: none; }
  .demo-presentation { display: block; padding: 0; }
  .demo-stage { border: 0; box-shadow: none; }
  .demo-step { display: block !important; break-after: page; min-height: auto; }
}