:root {
  color-scheme: dark;
  --bg: #0b0f16;
  --bg-soft: #101826;
  --panel: #141d2b;
  --panel-strong: #1d2a3d;
  --text: #f1f5f9;
  --muted: #c5cfdd;
  --subtle: #9aa8ba;
  --accent: #7dd3fc;
  --accent-strong: #38bdf8;
  --accent-soft: rgba(125, 211, 252, 0.12);
  --line: rgba(226, 232, 240, 0.14);
  --line-strong: rgba(226, 232, 240, 0.24);
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.34);
  --radius-lg: 28px;
  --radius-md: 20px;
  --page-width: 1120px;
  --measure: 68ch;
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at 14% 0%, rgba(56, 189, 248, 0.18), transparent 28rem),
    radial-gradient(circle at 88% 12%, rgba(20, 184, 166, 0.1), transparent 26rem),
    linear-gradient(180deg, #0d121c 0%, var(--bg) 36rem);
  font-size: 16px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  content: "";
  background-image:
    linear-gradient(rgba(226, 232, 240, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(226, 232, 240, 0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 82%);
}
.skip-link {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 50;
  padding: 10px 14px;
  border-radius: 999px;
  color: #03131d;
  background: var(--accent);
  font-weight: 800;
  text-decoration: none;
  transform: translateY(-160%);
}
.skip-link:focus { transform: translateY(0); }
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--line);
  background: rgba(11, 15, 22, 0.84);
  backdrop-filter: blur(18px);
}
.header-shell {
  width: min(var(--page-width), calc(100% - 40px));
  margin: 0 auto;
}
.nav-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.primary-nav {
  min-height: 72px;
}
.secondary-nav {
  min-height: 54px;
  border-top: 1px solid rgba(226, 232, 240, 0.08);
}
.brand,
.primary-nav a,
.secondary-nav a { color: var(--text); text-decoration: none; }
.brand { display: grid; gap: 1px; flex: 0 0 auto; font-weight: 850; letter-spacing: -0.02em; font-size: 20px; }
.brand small { color: var(--subtle); font-size: 0.76rem; font-weight: 650; letter-spacing: 0.01em; }
.label-short { display: none; }
.mobile-menu { display: none; }
.primary-links,
.secondary-links { display: flex; align-items: center; flex-wrap: wrap; }
.primary-links { gap: clamp(10px, 1.8vw, 18px); }
.secondary-links { margin-left: auto; gap: clamp(12px, 2.2vw, 22px); font-size: 0.95rem; font-weight: 650; }
.primary-links a,
.secondary-links a { min-height: 40px; display: inline-flex; align-items: center; }
.primary-links a {
  padding: 0 12px;
  border-radius: 999px;
  color: var(--muted);
  border: 1px solid transparent;
  /* Reserve the bold (800) width on every link so toggling .is-active never
     changes a link's measured width; the active state is distinguished by
     color + border + background, not by a weight bump. CSS-only fix. */
  font-weight: 800;
}
.primary-links a:hover,
.primary-links a:focus-visible {
  color: var(--text);
  border-color: var(--line);
  background: rgba(241, 245, 249, 0.045);
}
.primary-links a.is-active {
  color: var(--text);
  border-color: rgba(125, 211, 252, 0.34);
  background: rgba(125, 211, 252, 0.11);
}

.secondary-links a { color: var(--muted); }
.secondary-links a:hover,
.secondary-links a:focus-visible { color: var(--accent); }
:focus-visible { outline: 3px solid rgba(125, 211, 252, 0.65); outline-offset: 4px; }
.section-shell { width: min(var(--page-width), calc(100% - 40px)); margin: 0 auto; padding: clamp(64px, 9vw, 104px) 0; scroll-margin-top: 132px; }
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.12fr) minmax(320px, 0.88fr);
  min-height: min(820px, calc(100dvh - 126px));
  align-items: center;
  gap: clamp(36px, 7vw, 88px);
  padding-top: 48px;
}
.eyebrow { margin: 0 0 14px; color: var(--accent); font-size: 0.76rem; font-weight: 850; letter-spacing: 0.15em; text-transform: uppercase; }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { text-wrap: balance; }
h1 { max-width: 780px; margin-bottom: 22px; font-size: clamp(3rem, 7vw, 6.1rem); line-height: 0.98; letter-spacing: -0.07em; }
h2 { max-width: 820px; margin-bottom: 18px; font-size: clamp(2rem, 4.2vw, 4rem); line-height: 1.04; letter-spacing: -0.055em; }
h3 { margin-bottom: 12px; font-size: clamp(1.15rem, 1.7vw, 1.42rem); line-height: 1.2; letter-spacing: -0.03em; }
.hero-lede { max-width: 700px; margin-bottom: 0; color: var(--muted); font-size: clamp(1.12rem, 2vw, 1.42rem); line-height: 1.5; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.button { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; padding: 0 20px; border: 1px solid var(--line); border-radius: 999px; font-weight: 800; line-height: 1; text-decoration: none; transition: transform 180ms ease, border-color 180ms ease, background-color 180ms ease; white-space: nowrap; }
.button:hover,
.button:focus-visible { transform: translateY(-1px); }
.button:active { transform: translateY(1px); }
.button.primary { color: #03131d; background: var(--accent); border-color: var(--accent); }
.button.secondary { color: var(--text); background: rgba(241, 245, 249, 0.05); }
.button.ghost { color: var(--accent); background: transparent; border-color: transparent; padding-inline: 4px; }
.button.ghost:hover,
.button.ghost:focus-visible { border-color: var(--line); background: rgba(125, 211, 252, 0.08); }
.hero-panel,
.timeline-card,
.project-card,
.closing-block { border: 1px solid var(--line); border-radius: var(--radius-lg); box-shadow: var(--shadow); }
.hero-panel { position: relative; overflow: hidden; padding: clamp(24px, 4vw, 34px); background: linear-gradient(145deg, rgba(125, 211, 252, 0.12), rgba(20, 29, 43, 0.9) 46%), var(--panel); }
.hero-panel::before { position: absolute; inset: 0; content: ""; pointer-events: none; background: radial-gradient(circle at top right, rgba(125, 211, 252, 0.2), transparent 16rem); }
.panel-label,
.timeline-step,
.card-kicker { color: var(--accent); font-size: 0.76rem; font-weight: 850; letter-spacing: 0.1em; text-transform: uppercase; }
.panel-label { position: relative; margin-bottom: 24px; }
.signal-list { position: relative; display: grid; gap: 22px; margin: 0; padding: 0; list-style: none; }
.signal-list li { display: grid; gap: 6px; padding-top: 20px; border-top: 1px solid var(--line); }
.signal-list strong { font-size: 1.06rem; line-height: 1.2; }
.signal-list span { color: var(--muted); font-size: 1rem; }
.section-heading { max-width: 760px; margin-bottom: clamp(28px, 5vw, 46px); }
.section-heading.narrow { max-width: 700px; }
.section-heading.compact { max-width: 660px; margin-bottom: 22px; }
.section-heading p:not(.eyebrow) { max-width: 66ch; color: var(--muted); font-size: clamp(1.04rem, 1.4vw, 1.18rem); }
.narrative-section,
.lessons-section { border-top: 1px solid var(--line); }
.timeline-grid { display: grid; grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr); gap: 18px; align-items: stretch; }
.timeline-card { padding: clamp(24px, 4vw, 34px); background: rgba(20, 29, 43, 0.72); }
.timeline-card.elevated { background: linear-gradient(145deg, rgba(20, 29, 43, 0.92), rgba(29, 42, 61, 0.78)); }
.timeline-card p,
.project-card p,
.prose,
.lesson-list p { color: var(--muted); }
.timeline-card p,
.project-card p,
.prose p { max-width: var(--measure); }
.timeline-card p:last-child,
.project-card p:last-child,
.prose p:last-child,
.lesson-list p:last-child { margin-bottom: 0; }
.card-grid { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.95fr) minmax(0, 0.95fr); gap: 18px; }
.project-card { display: flex; min-height: 450px; flex-direction: column; padding: clamp(24px, 3vw, 30px); background: rgba(20, 29, 43, 0.82); }
.highlight-card { background: linear-gradient(150deg, rgba(56, 189, 248, 0.2), rgba(20, 29, 43, 0.95) 52%), var(--panel); }
.card-kicker { margin-bottom: 18px; }
.project-card ul { display: grid; gap: 10px; margin: auto 0 0; padding: 22px 0 0; border-top: 1px solid var(--line); color: var(--text); list-style-position: inside; }
.text-link { display: inline-flex; width: fit-content; min-height: 44px; align-items: center; gap: 6px; margin-top: 20px; color: var(--accent); font-weight: 800; text-decoration: none; }
.text-link:hover,
.text-link:focus-visible { color: var(--accent-strong); text-decoration: underline; text-underline-offset: 4px; }
.project-card li { padding-left: 2px; }
.lesson-list { display: grid; gap: 0; border-top: 1px solid var(--line); }
.lesson-list article { display: grid; grid-template-columns: 54px minmax(220px, 0.55fr) minmax(0, 1fr); gap: 22px; align-items: baseline; padding: 24px 0; border-bottom: 1px solid var(--line); }
.lesson-list span { color: var(--subtle); font-weight: 850; }
.closing-block { padding: clamp(34px, 6vw, 58px); background: radial-gradient(circle at 12% 0%, rgba(125, 211, 252, 0.16), transparent 22rem), rgba(20, 29, 43, 0.82); }
.closing-copy { display: grid; grid-template-columns: minmax(0, 0.88fr) minmax(0, 1.12fr); gap: clamp(28px, 6vw, 72px); align-items: start; }
.prose { font-size: 1.07rem; }

.site-footer {
  margin-top: clamp(56px, 9vw, 108px);
  padding: 0 0 clamp(28px, 5vw, 52px);
  background:
    radial-gradient(circle at 18% 0%, rgba(125, 211, 252, 0.08), transparent 20rem),
    linear-gradient(180deg, transparent, rgba(8, 12, 18, 0.72));
}

.footer-inner {
  position: relative;
  width: min(var(--page-width), calc(100% - 40px));
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 24px;
  padding: clamp(24px, 4vw, 34px);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 100% 0%, rgba(125, 211, 252, 0.14), transparent 18rem),
    linear-gradient(145deg, rgba(20, 29, 43, 0.92), rgba(13, 18, 28, 0.96));
  box-shadow: var(--shadow);
  overflow: hidden;
}

.footer-inner::before {
  position: absolute;
  inset: 0;
  content: "";
  pointer-events: none;
  background: linear-gradient(90deg, rgba(125, 211, 252, 0.12), transparent 42%);
  opacity: 0.7;
}

.footer-brand,
.footer-nav,
.footer-top {
  position: relative;
  z-index: 1;
}

.footer-brand {
  margin-right: auto;
  color: var(--text);
  font-size: clamp(1rem, 1.5vw, 1.18rem);
  font-weight: 850;
  letter-spacing: -0.02em;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.footer-nav a,
.footer-top {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  border: 1px solid transparent;
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
  transition: border-color 180ms ease, background-color 180ms ease, color 180ms ease, transform 180ms ease;
}

.footer-nav a {
  padding: 0 12px;
}

.footer-top {
  padding: 0 14px;
  border-color: rgba(125, 211, 252, 0.24);
  color: var(--accent);
  background: rgba(125, 211, 252, 0.08);
}

.footer-nav a:hover,
.footer-nav a:focus-visible,
.footer-top:hover,
.footer-top:focus-visible {
  color: var(--text);
  border-color: var(--line-strong);
  background: rgba(241, 245, 249, 0.055);
  transform: translateY(-1px);
}

/* Agent workflow page */
.appendix-hero { min-height: auto; padding-top: clamp(72px, 10vw, 118px); padding-bottom: clamp(56px, 8vw, 92px); }
.profile-map { position: relative; display: grid; gap: 18px; margin: 8px 0 24px; padding: clamp(18px, 3vw, 28px); border: 1px solid var(--line); border-radius: var(--radius-lg); background: linear-gradient(180deg, rgba(125, 211, 252, 0.055), rgba(20, 29, 43, 0.34)); overflow: hidden; }
.profile-map::before { position: absolute; inset: 0; content: ""; pointer-events: none; background: radial-gradient(circle at 50% 0%, rgba(125, 211, 252, 0.14), transparent 22rem); }
.profile-spine { position: absolute; top: 86px; bottom: calc(50% + 12px); left: 50%; width: 2px; transform: translateX(-50%); background: linear-gradient(var(--accent), var(--line-strong)); opacity: 0.75; }
.profile-node,
.feature-card,
.callout-card,
.table-card,
.decision-flow article { border: 1px solid var(--line); border-radius: var(--radius-md); background: rgba(20, 29, 43, 0.82); box-shadow: var(--shadow); }
.profile-node { position: relative; z-index: 1; padding: 22px; }
.profile-node span,
.feature-card span { display: block; margin-bottom: 8px; color: var(--accent); font-size: 0.74rem; font-weight: 850; letter-spacing: 0.1em; text-transform: uppercase; }
.profile-node strong,
.feature-card h3,
.callout-card h3 { display: block; color: var(--text); }
.profile-node p,
.feature-card p,
.callout-card p,
.decision-flow span { margin-bottom: 0; color: var(--muted); }
.profile-node p { font-size: 0.98rem; line-height: 1.55; }
.request-node,
.coordinator-node { max-width: 540px; margin-inline: auto; text-align: center; }
.request-node { background: rgba(20, 29, 43, 0.72); }
.coordinator-node { background: linear-gradient(145deg, rgba(125, 211, 252, 0.18), rgba(20, 29, 43, 0.94)); }
.profile-branches { position: relative; z-index: 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; min-height: 34px; margin: -2px 0 -8px; }
.profile-branches::before { position: absolute; top: 0; left: 12.5%; right: 12.5%; height: 2px; content: ""; background: var(--line-strong); }
.profile-branches span { position: relative; display: block; }
.profile-branches span::before { position: absolute; top: 0; left: 50%; width: 2px; height: 34px; content: ""; transform: translateX(-50%); background: linear-gradient(var(--line-strong), rgba(125, 211, 252, 0.42)); }
.profile-lanes { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
.lane-node { display: grid; align-content: start; min-height: 190px; }
.table-card { overflow-x: auto; margin-top: 28px; }
table { width: 100%; border-collapse: collapse; min-width: 760px; }
th,
td { padding: 16px 18px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
th { color: var(--text); font-size: 0.8rem; letter-spacing: 0.08em; text-transform: uppercase; }
td { color: var(--muted); line-height: 1.55; }
tr:last-child td { border-bottom: 0; }
code { color: var(--accent); font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace; font-size: 0.94em; }
.feature-section { border-top: 1px solid var(--line); }
.feature-grid.two-up { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.feature-card,
.callout-card { padding: clamp(24px, 4vw, 34px); }
.decision-flow { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; counter-reset: routing; }
.decision-flow article { position: relative; display: grid; gap: 10px; padding: 22px; }
.decision-flow article:not(:last-child)::after { position: absolute; top: 50%; right: -12px; z-index: 2; width: 22px; height: 2px; content: ""; background: var(--line-strong); }
.decision-flow strong { color: var(--text); line-height: 1.2; }
.decision-step { width: fit-content; padding: 4px 8px; border-radius: 999px; background: var(--accent-soft); color: var(--accent) !important; font-size: 0.74rem; font-weight: 850; letter-spacing: 0.08em; }
.callout-card { margin-top: 18px; background: radial-gradient(circle at 100% 0%, rgba(125, 211, 252, 0.14), transparent 18rem), rgba(20, 29, 43, 0.84); }
.callout-card .eyebrow { margin-bottom: 10px; }

/* Student Assignment Tracker case study */
.case-study-hero {
  min-height: auto;
  padding-top: clamp(68px, 9vw, 108px);
  padding-bottom: clamp(52px, 8vw, 88px);
}

.case-study-hero h1 {
  max-width: 920px;
  font-size: clamp(2.65rem, 4.2vw, 3.55rem);
  line-height: 1.04;
}

.case-summary {
  background:
    linear-gradient(145deg, rgba(125, 211, 252, 0.11), rgba(20, 29, 43, 0.94) 46%),
    var(--panel);
}

.snapshot-list {
  position: relative;
  display: grid;
  gap: 0;
  margin: 0;
}

.snapshot-list div {
  display: grid;
  gap: 5px;
  padding: 15px 0;
  border-top: 1px solid var(--line);
}

.snapshot-list div:first-child {
  padding-top: 0;
  border-top: 0;
}

.snapshot-list div:last-child {
  padding-bottom: 0;
}

.snapshot-list dt {
  color: var(--accent);
  font-size: 0.74rem;
  font-weight: 850;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.snapshot-list dd {
  margin: 0;
  color: var(--text);
  line-height: 1.45;
}

.case-overview,
.case-section {
  border-top: 1px solid var(--line);
}

.overview-grid {
  display: grid;
  grid-template-columns: 1.08fr 0.92fr 1fr;
  gap: 14px;
}

.overview-grid article {
  display: grid;
  align-content: start;
  gap: 9px;
  min-height: 210px;
  padding: clamp(22px, 3vw, 30px);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(20, 29, 43, 0.68);
}

.overview-grid article:first-child {
  background:
    radial-gradient(circle at 100% 0%, rgba(125, 211, 252, 0.15), transparent 16rem),
    rgba(20, 29, 43, 0.86);
}

.overview-grid span,
.feature-card span {
  color: var(--accent);
  font-size: 0.74rem;
  font-weight: 850;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.overview-grid strong {
  color: var(--text);
  font-size: clamp(1.08rem, 1.8vw, 1.35rem);
  line-height: 1.18;
  letter-spacing: -0.025em;
}

.overview-grid p {
  margin-bottom: 0;
  color: var(--muted);
}

.cottage-overview-grid {
  grid-template-columns: 1.05fr 0.95fr 1fr;
}

.cottage-overview-grid article {
  min-height: 232px;
}

.case-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.42fr);
  gap: clamp(28px, 6vw, 72px);
  align-items: start;
}

.case-layout.flipped {
  grid-template-columns: minmax(280px, 0.42fr) minmax(0, 1fr);
}

.case-layout.flipped .case-copy {
  grid-column: 2;
}

.case-layout.flipped .fact-card {
  grid-column: 1;
  grid-row: 1;
}

.case-copy p {
  max-width: var(--measure);
  color: var(--muted);
  font-size: 1.07rem;
}

.fact-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: clamp(24px, 4vw, 34px);
  background: rgba(20, 29, 43, 0.82);
  box-shadow: var(--shadow);
}

.compact-list {
  display: grid;
  gap: 11px;
  margin: 0;
  padding: 0;
  color: var(--text);
  list-style: none;
}

.compact-list li {
  position: relative;
  padding-left: 18px;
}

.compact-list li::before {
  position: absolute;
  top: 0.72em;
  left: 0;
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: var(--accent);
  content: "";
}

.accent-card {
  background:
    radial-gradient(circle at 100% 0%, rgba(125, 211, 252, 0.14), transparent 18rem),
    rgba(20, 29, 43, 0.84);
}

.feature-grid.three-up {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.case-feature-grid .feature-card {
  min-height: 300px;
}

.case-feature-grid article {
  display: grid;
  align-content: start;
  gap: 9px;
  min-height: 220px;
  padding: clamp(22px, 3vw, 30px);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(20, 29, 43, 0.68);
}

.case-feature-grid article:nth-child(2) {
  background:
    radial-gradient(circle at 100% 0%, rgba(125, 211, 252, 0.12), transparent 16rem),
    rgba(20, 29, 43, 0.82);
}

.case-feature-grid strong {
  color: var(--text);
  font-size: clamp(1.08rem, 1.8vw, 1.32rem);
  line-height: 1.18;
  letter-spacing: -0.02em;
}

.case-feature-grid p {
  margin-bottom: 0;
  color: var(--muted);
}

.case-flow article {
  min-height: 210px;
}

.linked-card {
  outline: 1px solid rgba(125, 211, 252, 0.18);
  background:
    radial-gradient(circle at 100% 0%, rgba(125, 211, 252, 0.11), transparent 16rem),
    rgba(20, 29, 43, 0.82);
}

@media (max-width: 980px) {
  .hero,
  .timeline-grid,
  .card-grid,
  .closing-copy,
  .case-layout,
  .case-layout.flipped,
  .overview-grid,
  .feature-grid.three-up { grid-template-columns: 1fr; }
  .hero { min-height: auto; padding-top: 72px; }
  .project-card { min-height: auto; }
  .primary-nav { min-height: 58px; }
  .secondary-nav { min-height: 42px; }
  .nav-row { gap: 16px; }
  .primary-links { gap: 8px; font-size: 0.9rem; }
  .secondary-links { gap: 12px; font-size: 0.86rem; }
  .primary-links a { min-height: 36px; padding: 0 9px; }
  .secondary-links a { min-height: 34px; }
  .label-full { display: none; }
  .label-short { display: inline; }
  .profile-lanes,
  .decision-flow { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .profile-branches { display: none; }
  .profile-spine { display: none; }
  .lane-node { min-height: 0; }
  .decision-flow article:not(:last-child)::after { display: none; }
  .feature-grid.two-up { grid-template-columns: 1fr; }
  .case-layout.flipped .case-copy,
  .case-layout.flipped .fact-card { grid-column: auto; grid-row: auto; }
}
@media (max-width: 820px) {
  .header-shell { width: min(var(--page-width), calc(100% - 28px)); }
  .nav-row { align-items: center; flex-direction: row; gap: 12px; }
  .primary-nav { min-height: auto; padding: 12px 0; }
  .secondary-nav,
  .primary-links { display: none; }
  .mobile-menu { position: relative; z-index: 40; display: block; margin-left: auto; }
  .mobile-menu summary {
    display: inline-flex;
    min-height: 38px;
    align-items: center;
    gap: 8px;
    padding: 0 14px;
    border: 1px solid rgba(125, 211, 252, 0.28);
    border-radius: 999px;
    color: var(--accent);
    background: rgba(125, 211, 252, 0.08);
    font-size: 0.88rem;
    font-weight: 800;
    line-height: 1;
    list-style: none;
    cursor: pointer;
  }
  .mobile-menu summary::-webkit-details-marker { display: none; }
  .mobile-menu summary::after { content: "☰"; font-size: 0.9rem; }
  .mobile-menu[open] summary::after { content: "×"; font-size: 1.05rem; }
  .mobile-menu-panel {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    z-index: 60;
    display: grid;
    width: min(84vw, 360px);
    gap: 18px;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    background:
      radial-gradient(circle at 100% 0%, rgba(125, 211, 252, 0.14), transparent 15rem),
      rgba(20, 29, 43, 0.98);
    box-shadow: var(--shadow);
  }
  .mobile-menu-panel nav { display: flex; flex-wrap: wrap; gap: 8px; }
  .mobile-menu-label {
    width: 100%;
    margin: 0 0 2px;
    color: var(--accent);
    font-size: 0.72rem;
    font-weight: 850;
    letter-spacing: 0.1em;
    text-transform: uppercase;
  }
  .mobile-menu-panel a {
    display: inline-flex;
    min-height: 36px;
    align-items: center;
    padding: 0 11px;
    border: 1px solid var(--line);
    border-radius: 999px;
    color: var(--muted);
    background: rgba(241, 245, 249, 0.035);
    font-size: 0.86rem;
    font-weight: 750;
    line-height: 1;
    text-decoration: none;
  }
  .mobile-menu-panel a:hover,
  .mobile-menu-panel a:focus-visible {
    color: var(--text);
    border-color: rgba(125, 211, 252, 0.34);
    background: rgba(125, 211, 252, 0.1);
  }
  .section-shell { width: min(var(--page-width), calc(100% - 28px)); padding: 56px 0; scroll-margin-top: 88px; }
  .footer-inner { width: min(var(--page-width), calc(100% - 28px)); }
  .hero { gap: 26px; padding-top: 48px; }
  h1 { font-size: clamp(2.8rem, 14vw, 4.35rem); letter-spacing: -0.064em; }
  h2 { font-size: clamp(2rem, 10vw, 3.1rem); }
  .hero-lede { font-size: 1.08rem; }
  .button { width: 100%; }
  .lesson-list article { grid-template-columns: 1fr; gap: 6px; }
  .hero-panel,
  .timeline-card,
  .project-card,
  .closing-block,
  .profile-node,
  .feature-card,
  .callout-card,
  .fact-card,
  .decision-flow article { border-radius: 22px; }
  .profile-lanes,
  .decision-flow { grid-template-columns: 1fr; }
  .table-card { margin-inline: -14px; border-radius: 0; border-left: 0; border-right: 0; }
}
@media (max-width: 640px) {
  .footer-inner {
    align-items: flex-start;
    gap: 12px 18px;
  }

  .footer-brand,
  .footer-nav,
  .footer-top {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after { scroll-behavior: auto !important; transition-duration: 0.001ms !important; animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; }
}

@media (max-width: 420px) {
  h1 { font-size: clamp(2.35rem, 13vw, 3.35rem); }
  .hero-actions { gap: 10px; }
  .profile-map { padding: 14px; }
}