/* CAUSAL-FOREST-UNIT-ABDUCTION-STYLE-2026-07-17-V1 */
:root {
  --paper: #f5f1e8;
  --paper-2: #fbfaf6;
  --ink: #18202b;
  --ink-soft: #455267;
  --muted: #6b7481;
  --line: rgba(24, 32, 43, 0.15);
  --blue: #2b59d6;
  --blue-deep: #193d9d;
  --blue-soft: #e8eefc;
  --orange: #e25b2b;
  --orange-deep: #a93817;
  --orange-soft: #fbe9df;
  --navy: #18202b;
  --white: #fff;
  --serif: Georgia, "Songti SC", "STSong", serif;
  --sans: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --shadow: 0 26px 70px rgba(28, 35, 50, 0.11);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--paper);
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 88% 4%, rgba(43, 89, 214, 0.08), transparent 27rem),
    var(--paper);
  font-family: var(--sans);
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

a { color: inherit; }

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

.wrap {
  width: min(1180px, calc(100% - 48px));
  margin-inline: auto;
}

.hero-grid > *,
.one-minute > *,
.thesis-pair > *,
.section-head > *,
.bridge-visual > *,
.prose-grid > *,
.boundary-grid > *,
.subpopulation-grid > *,
.operator-legend > *,
.instantiation-grid > *,
.warning-grid > *,
.theorem-boundary > *,
.agenda-grid > *,
.references-grid > * {
  min-width: 0;
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: 10px;
  left: 10px;
  padding: 10px 14px;
  color: white;
  background: var(--navy);
  border-radius: 8px;
  transform: translateY(-180%);
}

.skip-link:focus { transform: translateY(0); }

.topbar {
  position: sticky;
  z-index: 50;
  top: 0;
  border-bottom: 1px solid rgba(24, 32, 43, 0.1);
  background: rgba(245, 241, 232, 0.9);
  backdrop-filter: blur(18px);
}

.topbar-inner {
  width: min(1260px, calc(100% - 36px));
  min-height: 70px;
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  min-width: max-content;
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
}

.brand-mark {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  color: white;
  background: var(--navy);
  border-radius: 50%;
  font-family: var(--serif);
  font-size: 15px;
}

.brand strong,
.brand small { display: block; }

.brand strong {
  font-size: 12px;
  letter-spacing: 0.04em;
}

.brand small {
  margin-top: 1px;
  color: var(--muted);
  font-size: 9px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.topnav {
  display: flex;
  align-items: center;
  gap: 22px;
  overflow-x: auto;
  scrollbar-width: none;
  white-space: nowrap;
}

.topnav::-webkit-scrollbar { display: none; }

.topnav a {
  color: var(--ink-soft);
  font-size: 12px;
  font-weight: 680;
  text-decoration: none;
}

.topnav a:hover { color: var(--blue); }

.hero {
  padding: clamp(72px, 10vw, 132px) 0 82px;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.48fr) minmax(300px, 0.72fr);
  align-items: end;
  gap: clamp(44px, 8vw, 110px);
}

.eyebrow {
  margin: 0 0 16px;
  color: var(--orange);
  font-size: 10px;
  font-weight: 850;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.hero h1,
.section h2,
.one-minute h2,
.closing h2 {
  font-family: var(--serif);
  font-weight: 500;
  letter-spacing: -0.035em;
}

.hero h1 {
  max-width: 900px;
  margin: 0;
  font-size: clamp(52px, 7.7vw, 104px);
  line-height: 0.98;
}

.hero h1 em {
  color: var(--blue);
  font-style: normal;
}

.hero-deck {
  max-width: 760px;
  margin: 30px 0 0;
  color: var(--ink-soft);
  font-family: var(--serif);
  font-size: clamp(18px, 2.2vw, 28px);
  line-height: 1.35;
}

.hero-lead {
  max-width: 810px;
  margin: 24px 0 0;
  color: var(--ink-soft);
  font-size: 16px;
  line-height: 1.82;
}

.hero-lead strong { color: var(--ink); }

.hero-actions,
.closing-actions {
  margin-top: 30px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.button {
  min-height: 45px;
  padding: 11px 17px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 12px;
  font-weight: 760;
  text-decoration: none;
  transition: transform 0.18s ease, background 0.18s ease, color 0.18s ease;
}

.button:hover { transform: translateY(-2px); }

.button.primary {
  color: white;
  border-color: var(--blue);
  background: var(--blue);
}

.button.primary:hover { background: var(--blue-deep); }

.button.ghost { background: rgba(255, 255, 255, 0.48); }

.button.ghost:hover { background: white; }

.hero-aside {
  position: relative;
  padding: 30px;
  color: white;
  background: var(--navy);
  border-radius: 24px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.hero-aside::after {
  content: "";
  position: absolute;
  right: -55px;
  bottom: -70px;
  width: 190px;
  height: 190px;
  border: 35px solid rgba(43, 89, 214, 0.52);
  border-radius: 50%;
}

.aside-label {
  position: relative;
  z-index: 1;
  margin: 0;
  color: #9eb7ff;
  font-size: 9px;
  font-weight: 850;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.mini-pipeline {
  position: relative;
  z-index: 1;
  margin: 23px 0;
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  align-items: center;
  gap: 7px;
}

.mini-pipeline span {
  min-height: 54px;
  padding: 9px 7px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255, 255, 255, 0.17);
  border-radius: 10px;
  color: #dfe7ff;
  font-size: 9px;
  line-height: 1.35;
  text-align: center;
}

.mini-pipeline i {
  color: var(--orange);
  font-style: normal;
}

.hero-aside > p:not(.aside-label) {
  position: relative;
  z-index: 1;
  margin: 0;
  color: #cbd2dc;
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.5;
}

.hero-aside strong { color: white; }

.boundary-pill {
  position: relative;
  z-index: 1;
  width: fit-content;
  margin-top: 22px;
  padding: 7px 10px;
  color: #ffd7c6;
  background: rgba(226, 91, 43, 0.16);
  border: 1px solid rgba(226, 91, 43, 0.48);
  border-radius: 999px;
  font-size: 9px;
  font-weight: 750;
  letter-spacing: 0.04em;
}

.one-minute {
  margin-bottom: 72px;
  padding: 36px;
  display: grid;
  grid-template-columns: 70px minmax(250px, 0.66fr) minmax(0, 1.34fr);
  gap: 30px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section-number {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  color: white;
  background: var(--navy);
  border-radius: 50%;
  font-family: var(--serif);
  font-size: 13px;
}

.one-minute h2,
.section h2 {
  margin: 0;
  font-size: clamp(36px, 5vw, 66px);
  line-height: 1.08;
}

.lead {
  color: var(--ink-soft);
  font-size: 17px;
  line-height: 1.8;
}

.one-minute .lead { margin: 18px 0 0; }

.thesis-pair {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.thesis-pair article {
  min-height: 190px;
  padding: 25px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.48);
}

.thesis-pair article:last-child {
  background: var(--orange-soft);
  border-color: rgba(226, 91, 43, 0.3);
}

.thesis-pair span,
.instantiation-grid > article > span,
.agenda-grid > article > span {
  color: var(--blue);
  font-size: 9px;
  font-weight: 850;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.thesis-pair article:last-child span { color: var(--orange-deep); }

.thesis-pair h3,
.instantiation-grid h3,
.warning-grid h3,
.agenda-grid h3 {
  margin: 20px 0 10px;
  font-family: var(--serif);
  font-size: 24px;
  line-height: 1.2;
}

.thesis-pair p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 13px;
}

.section { padding: clamp(80px, 10vw, 132px) 0; }

.section-tint {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.48);
}

.section-head {
  margin-bottom: 54px;
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(280px, 0.75fr);
  align-items: end;
  gap: 50px;
}

.section-head > p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.section-head.narrow { margin-inline: auto; }

.bridge-visual {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 100px minmax(0, 1fr);
  align-items: center;
  gap: 24px;
}

.lane {
  min-width: 0;
  padding: 26px;
  border: 1px solid rgba(43, 89, 214, 0.22);
  border-radius: 24px;
  background: linear-gradient(155deg, #fff, var(--blue-soft));
}

.abduction-lane {
  border-color: rgba(226, 91, 43, 0.28);
  background: linear-gradient(155deg, #fff, var(--orange-soft));
}

.lane-label {
  margin-bottom: 25px;
  color: var(--blue-deep);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.abduction-lane .lane-label { color: var(--orange-deep); }

.lane-label span {
  margin-right: 8px;
  opacity: 0.58;
}

.node {
  min-height: 88px;
  padding: 17px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(24, 32, 43, 0.14);
  border-radius: 15px;
  background: rgba(255, 255, 255, 0.72);
  text-align: center;
}

.node small {
  color: var(--muted);
  font-size: 9px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.node strong {
  font-family: var(--serif);
  font-size: 23px;
  font-weight: 500;
}

.arrow {
  height: 42px;
  display: grid;
  place-items: center;
  color: var(--muted);
}

.candidate-cloud {
  min-height: 122px;
  padding: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  border: 1px dashed rgba(24, 32, 43, 0.2);
  border-radius: 50%;
}

.candidate-cloud span {
  width: 57px;
  height: 57px;
  display: grid;
  place-items: center;
  color: white;
  background: rgba(43, 89, 214, var(--w));
  border: 1px solid rgba(43, 89, 214, 0.7);
  border-radius: 50%;
  font-size: 9px;
  text-align: center;
}

.latent-cloud span {
  background: rgba(226, 91, 43, var(--w));
  border-color: rgba(169, 56, 23, 0.7);
}

.weight-label {
  margin: 13px 0 0;
  color: var(--ink-soft);
  font-size: 11px;
  text-align: center;
}

.bridge-axis {
  min-height: 180px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: 9px;
  font-weight: 820;
  letter-spacing: 0.1em;
  text-align: center;
  text-transform: uppercase;
}

.bridge-axis::before,
.bridge-axis::after {
  content: "";
  width: 1px;
  height: 60px;
  background: var(--line);
}

.bridge-axis i {
  margin: 8px 0;
  color: var(--orange);
  font-family: var(--serif);
  font-size: 30px;
  font-style: normal;
}

.visual-caption {
  max-width: 780px;
  margin: 28px auto 0;
  color: var(--muted);
  font-size: 12px;
  text-align: center;
}

.prose-grid {
  display: grid;
  grid-template-columns: 120px minmax(0, 820px);
  justify-content: center;
  gap: 55px;
}

.margin-note {
  padding-top: 8px;
  color: var(--blue);
}

.margin-note.orange { color: var(--orange); }

.margin-note span {
  width: 45px;
  height: 45px;
  display: grid;
  place-items: center;
  color: white;
  background: currentColor;
  border-radius: 50%;
  font-family: var(--serif);
  font-size: 12px;
}

.margin-note p {
  margin: 20px 0 0;
  font-size: 9px;
  font-weight: 820;
  letter-spacing: 0.12em;
  line-height: 1.5;
  text-transform: uppercase;
  writing-mode: vertical-rl;
}

.prose-main h2 { max-width: 780px; }

.prose-main > p:not(.eyebrow):not(.lead) {
  margin: 28px 0 0;
  color: var(--ink-soft);
  font-size: 15px;
}

.formula-card {
  width: 100%;
  max-width: 100%;
  margin: 30px 0;
  padding: 30px 24px;
  color: white;
  background: var(--blue);
  border-radius: 18px;
  overflow-x: auto;
  overscroll-behavior-inline: contain;
}

.formula-card.orange { background: var(--orange); }

.formula-card.compact { padding-block: 24px; }

.formula-card.paper {
  color: var(--ink);
  background: white;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.formula-card mjx-container[display="true"] { margin: 0 !important; }

.callout {
  margin: 32px 0;
  padding: 22px 24px;
  border-left: 4px solid var(--blue);
  background: var(--blue-soft);
}

.callout strong {
  color: var(--blue-deep);
  font-size: 12px;
}

.callout p {
  margin: 8px 0 0;
  color: var(--ink-soft);
  font-size: 13px;
}

.plain-language {
  margin-top: 34px;
  padding: 22px;
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 20px;
  border-top: 1px solid rgba(43, 89, 214, 0.35);
  border-bottom: 1px solid rgba(43, 89, 214, 0.35);
}

.plain-language.orange { border-color: rgba(226, 91, 43, 0.4); }

.plain-language span {
  color: var(--blue);
  font-size: 10px;
  font-weight: 850;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.plain-language.orange span { color: var(--orange-deep); }

.plain-language p {
  margin: 0;
  color: var(--ink-soft);
  font-family: var(--serif);
  font-size: 18px;
}

.section-dark {
  color: white;
  background: var(--navy);
}

.section-dark .eyebrow { color: #ff946c; }

.section-dark h2 { color: white; }

.boundary-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
  gap: clamp(40px, 8vw, 110px);
}

.boundary-grid > div:last-child {
  padding-left: 32px;
  border-left: 1px solid rgba(255, 255, 255, 0.17);
}

.boundary-grid p {
  margin: 0 0 22px;
  color: #c7ced9;
  font-size: 15px;
}

.boundary-grid strong { color: white; }

.same-token-rule {
  margin: 30px 0;
  padding: 25px;
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1.2fr;
  align-items: center;
  gap: 14px;
  background: var(--navy);
  border-radius: 18px;
  color: white;
}

.same-token-rule > div:not(.query-stack) {
  min-height: 74px;
  padding: 12px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 12px;
}

.same-token-rule small {
  color: #aeb8c9;
  font-size: 8px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.same-token-rule i {
  color: var(--orange);
  font-style: normal;
}

.query-stack {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
}

.query-stack span {
  min-height: 52px;
  display: grid;
  place-items: center;
  color: white;
  background: rgba(226, 91, 43, 0.32);
  border: 1px solid rgba(226, 91, 43, 0.58);
  border-radius: 10px;
}

.subpopulation-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.84fr) minmax(0, 1.16fr);
  align-items: center;
  gap: clamp(50px, 8vw, 110px);
}

.subpopulation-grid > div:first-child > p:not(.eyebrow) {
  color: var(--ink-soft);
  font-size: 15px;
}

.three-qualifiers {
  margin: 16px 0 0;
  padding: 0;
  display: grid;
  gap: 9px;
  list-style: none;
}

.three-qualifiers li {
  padding: 13px 15px;
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 16px;
  border-bottom: 1px solid var(--line);
}

.three-qualifiers strong {
  color: var(--orange-deep);
  font-size: 12px;
}

.three-qualifiers span {
  color: var(--ink-soft);
  font-size: 12px;
}

.operator-card {
  color: white;
  background: var(--navy);
  border-radius: 26px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.operator-formula {
  padding: clamp(30px, 6vw, 66px);
  overflow-x: auto;
}

.operator-formula mjx-container[display="true"] { margin: 0 !important; }

.operator-legend {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}

.operator-legend div {
  min-height: 92px;
  padding: 18px;
  border-right: 1px solid rgba(255, 255, 255, 0.12);
}

.operator-legend div:last-child { border-right: 0; }

.operator-legend span {
  color: #9eb7ff;
  font-family: var(--serif);
  font-size: 17px;
}

.operator-legend p {
  margin: 8px 0 0;
  color: #aeb8c9;
  font-size: 9px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.instantiation-grid {
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.instantiation-grid article {
  padding: 30px;
  border: 1px solid rgba(43, 89, 214, 0.22);
  border-radius: 20px;
  background: var(--blue-soft);
}

.instantiation-grid article:last-child {
  border-color: rgba(226, 91, 43, 0.28);
  background: var(--orange-soft);
}

.instantiation-grid article:last-child > span { color: var(--orange-deep); }

.instantiation-grid p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 13px;
}

blockquote {
  max-width: 900px;
  margin: 70px auto 0;
  padding: 0;
  color: var(--ink);
  font-family: var(--serif);
  font-size: clamp(28px, 4.2vw, 52px);
  line-height: 1.28;
  text-align: center;
}

blockquote::before {
  content: "“";
  display: block;
  color: var(--orange);
  font-size: 90px;
  line-height: 0.65;
}

.comparison-wrap {
  max-width: 100%;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: white;
  overflow-x: auto;
  box-shadow: var(--shadow);
}

.comparison-wrap:focus-visible {
  outline: 3px solid rgba(43, 89, 214, 0.35);
  outline-offset: 4px;
}

table {
  width: 100%;
  min-width: 780px;
  border-collapse: collapse;
  font-size: 12px;
}

th,
td {
  padding: 18px 20px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

thead th {
  color: white;
  background: var(--navy);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

thead th:nth-child(2) { background: var(--blue-deep); }
thead th:nth-child(3) { background: var(--orange-deep); }

tbody th {
  width: 20%;
  color: var(--ink);
  background: #faf9f5;
  font-weight: 750;
}

tbody td {
  width: 40%;
  color: var(--ink-soft);
}

tbody tr:last-child th,
tbody tr:last-child td { border-bottom: 0; }

.warning-grid {
  margin-top: 22px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.warning-grid article {
  min-height: 210px;
  padding: 24px;
  border-top: 3px solid var(--orange);
  background: var(--paper-2);
}

.warning-grid article > span {
  color: var(--orange-deep);
  font-size: 9px;
  font-weight: 850;
}

.warning-grid h3 { font-size: 19px; }

.warning-grid p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 12px;
}

.theorem-boundary {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
  align-items: start;
  gap: clamp(50px, 8vw, 110px);
}

.verdict-card {
  padding: 36px;
  border: 1px solid rgba(226, 91, 43, 0.3);
  border-radius: 22px;
  background: var(--orange-soft);
}

.verdict {
  display: inline-flex;
  padding: 7px 10px;
  color: white;
  background: var(--orange-deep);
  border-radius: 999px;
  font-size: 9px;
  font-weight: 850;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.verdict-card p,
.verdict-card li {
  color: var(--ink-soft);
  font-size: 13px;
}

.verdict-card p { margin: 22px 0 0; }

.verdict-card ul {
  margin: 20px 0 0;
  padding-left: 18px;
}

.verdict-card li + li { margin-top: 8px; }

.agenda-section {
  color: white;
  background: var(--blue-deep);
}

.section-head.light h2 { color: white; }

.section-head.light > p { color: #c7d3f7; }

.agenda-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.agenda-grid article {
  min-height: 270px;
  padding: 28px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.08);
}

.agenda-grid > article > span { color: #ffac8d; }

.agenda-grid h3 { color: white; }

.agenda-grid p {
  margin: 0;
  color: #d3dbf4;
  font-size: 13px;
}

.references-section { padding-bottom: 100px; }

.references-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.62fr) minmax(0, 1.38fr);
  gap: clamp(40px, 8vw, 100px);
}

.references-grid ol {
  margin: 0;
  padding-left: 22px;
}

.references-grid li {
  padding: 15px 0 15px 10px;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line);
  font-size: 13px;
}

.references-grid a {
  color: var(--blue-deep);
  text-underline-offset: 3px;
}

.closing {
  padding: clamp(80px, 12vw, 150px) 0;
  color: white;
  background: var(--orange);
}

.closing-inner { text-align: center; }

.closing p {
  margin: 0 0 20px;
  font-size: 10px;
  font-weight: 850;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.closing h2 {
  max-width: 900px;
  margin: 0 auto;
  font-size: clamp(40px, 6.6vw, 82px);
  line-height: 1.08;
}

.closing-actions { justify-content: center; }

.light-button {
  color: var(--orange-deep);
  border-color: white;
  background: white;
}

.line-button {
  color: white;
  border-color: rgba(255, 255, 255, 0.55);
}

footer {
  padding: 34px 0;
  color: white;
  background: var(--navy);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.footer-inner strong { font-family: var(--serif); }

.footer-inner p {
  margin: 3px 0 0;
  color: #9fa9b9;
  font-size: 10px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 15px;
}

.footer-links a {
  color: #c5cedc;
  font-size: 10px;
  text-decoration: none;
}

.footer-links a:hover { color: white; }

mjx-container {
  max-width: 100%;
  overflow-x: auto;
  overflow-y: hidden;
}

@media (max-width: 980px) {
  .topbar-inner { width: min(100% - 26px, 1180px); }
  .topnav { max-width: 54vw; }
  .hero-grid,
  .section-head,
  .subpopulation-grid,
  .theorem-boundary,
  .references-grid { grid-template-columns: minmax(0, 1fr); }
  .hero-aside { max-width: 620px; }
  .one-minute { grid-template-columns: 55px 1fr; }
  .thesis-pair { grid-column: 2; }
  .bridge-visual { grid-template-columns: 1fr 68px 1fr; gap: 14px; }
  .candidate-cloud span { width: 46px; height: 46px; font-size: 8px; }
  .warning-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .operator-legend { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .operator-legend div { border-bottom: 1px solid rgba(255, 255, 255, 0.12); }
}

@media (max-width: 760px) {
  .wrap { width: min(100% - 30px, 1180px); }
  .topbar-inner { min-height: 62px; }
  .brand small { display: none; }
  .topnav { max-width: 48vw; gap: 16px; }
  .topnav a { font-size: 10px; }
  .hero { padding: 62px 0 58px; }
  .hero-grid { gap: 38px; }
  .hero h1 { font-size: clamp(46px, 14vw, 74px); }
  .hero-deck { margin-top: 22px; }
  .hero-lead { font-size: 14px; }
  .hero-actions .button { flex: 1 1 190px; }
  .one-minute {
    width: min(100% - 30px, 1180px);
    padding: 28px 0;
    grid-template-columns: 1fr;
  }
  .thesis-pair { grid-column: auto; }
  .section-number { width: 42px; height: 42px; }
  .section { padding: 78px 0; }
  .section h2,
  .one-minute h2 { font-size: clamp(34px, 10vw, 52px); }
  .section-head { gap: 24px; margin-bottom: 38px; }
  .bridge-visual { grid-template-columns: 1fr; }
  .bridge-axis {
    min-height: auto;
    flex-direction: row;
    gap: 12px;
  }
  .bridge-axis::before,
  .bridge-axis::after { width: 45px; height: 1px; }
  .bridge-axis i { margin: 0; }
  .prose-grid { grid-template-columns: minmax(0, 1fr); gap: 20px; }
  .margin-note { display: flex; align-items: center; gap: 12px; }
  .margin-note p { margin: 0; writing-mode: initial; }
  .boundary-grid { grid-template-columns: 1fr; gap: 35px; }
  .boundary-grid > div:last-child { padding: 28px 0 0; border-left: 0; border-top: 1px solid rgba(255, 255, 255, 0.17); }
  .same-token-rule { grid-template-columns: 1fr; }
  .same-token-rule > i { transform: rotate(90deg); text-align: center; }
  .three-qualifiers li { grid-template-columns: 1fr; gap: 4px; }
  .operator-legend { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .instantiation-grid,
  .agenda-grid { grid-template-columns: 1fr; }
  .agenda-grid article { min-height: auto; }
  .footer-inner { align-items: flex-start; flex-direction: column; }
  .footer-links { justify-content: flex-start; }
}

@media (max-width: 520px) {
  .topbar-inner { width: calc(100% - 20px); }
  .brand strong { max-width: 130px; font-size: 10px; }
  .brand-mark { width: 30px; height: 30px; }
  .topnav { max-width: 42vw; }
  .hero h1 { font-size: 44px; }
  .hero-deck { font-size: 18px; }
  .hero-aside,
  .lane,
  .verdict-card { padding: 22px; border-radius: 18px; }
  .mini-pipeline { grid-template-columns: 1fr; }
  .mini-pipeline i { transform: rotate(90deg); text-align: center; }
  .thesis-pair { grid-template-columns: 1fr; }
  .formula-card { padding: 24px 16px; border-radius: 14px; }
  .plain-language { grid-template-columns: 1fr; gap: 8px; }
  .candidate-cloud { border-radius: 30px; }
  .warning-grid { grid-template-columns: 1fr; }
  .warning-grid article { min-height: auto; }
  .operator-legend { grid-template-columns: 1fr; }
  .operator-legend div { min-height: 76px; border-right: 0; }
  blockquote { font-size: 29px; }
  .closing h2 { font-size: 42px; }
  .closing-actions .button { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; }
}