:root {
  color-scheme: light;
  --ink: #14243a;
  --ink-soft: #526174;
  --navy: #102a43;
  --blue: #176b87;
  --teal: #0a7b72;
  --orange: #e66a2c;
  --paper: #ffffff;
  --canvas: #eef4f7;
  --line: #cbd9e2;
  --line-dark: #9fb3c1;
  --focus: #f4a261;
  --shadow: 0 18px 50px rgba(16, 42, 67, 0.12);
  --radius: 18px;
  font-family: Inter, 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(--ink);
  background: var(--canvas);
  font-size: 1rem;
  line-height: 1.6;
}

a { color: inherit; }

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

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

.site-header {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 0.8rem 5vw 0.7rem;
  color: #fff;
  background: var(--navy);
  border-bottom: 3px solid var(--orange);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.08rem;
  font-weight: 760;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 2.25rem;
  height: 2.25rem;
  border: 1px solid rgba(255, 255, 255, 0.6);
  border-radius: 9px 9px 9px 2px;
  color: var(--navy);
  background: #fff;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.55rem;
}

.site-nav a {
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0.48rem 0.82rem;
  border: 1px solid rgba(255, 255, 255, 0.24);
  border-radius: 9px;
  color: #dcebf3;
  background: rgba(255, 255, 255, 0.06);
  font-size: 0.86rem;
  font-weight: 720;
  text-decoration: none;
  white-space: nowrap;
}

.site-nav a:hover {
  border-color: rgba(255, 255, 255, 0.65);
  color: #fff;
  background: rgba(255, 255, 255, 0.16);
}

main {
  width: min(1100px, 90vw);
  margin: 0 auto;
  padding: 4.25rem 0 4.5rem;
}

.intro { max-width: 1100px; }

.eyebrow {
  margin: 0 0 0.6rem;
  color: var(--teal);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1, h2, h3 {
  margin-top: 0;
  line-height: 1.15;
  letter-spacing: -0.025em;
}

h1 {
  max-width: 1100px;
  margin-bottom: 1rem;
  font-size: clamp(2.25rem, 4.3vw, 3.4rem);
  text-wrap: balance;
}

.intro-copy {
  max-width: 800px;
  margin: 0;
  color: var(--ink-soft);
  font-size: 1.08rem;
}

.collection-summary {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  margin: 2rem 0 0;
}

.collection-summary div {
  display: flex;
  align-items: baseline;
  gap: 0.55rem;
  padding: 0.2rem 1.25rem;
  border-left: 1px solid var(--line-dark);
}

.collection-summary div:first-child { padding-left: 0; border-left: 0; }
.collection-summary dt { color: var(--navy); font-size: 1.35rem; font-weight: 850; }
.collection-summary dd { margin: 0; color: var(--ink-soft); font-size: 0.88rem; font-weight: 700; }

.labs-section { margin-top: 4.5rem; scroll-margin-top: 1rem; }

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  margin-bottom: 1.15rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--line-dark);
}

.section-heading .eyebrow { margin: 0; }
.section-heading h2 { margin: 0; font-size: 1.55rem; }

.lab-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  grid-auto-rows: 1fr;
  gap: 1.35rem;
}

.lab-card {
  min-width: 0;
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow);
}

.card-band {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 1.35rem;
  color: #fff;
  background: var(--teal);
}

.computational-card .card-band { background: var(--blue); }

.card-band span {
  display: grid;
  place-items: center;
  width: 2.65rem;
  height: 2.65rem;
  border: 1px solid rgba(255, 255, 255, 0.72);
  border-radius: 10px 10px 10px 3px;
  font-size: 0.82rem;
  font-weight: 850;
  letter-spacing: 0.08em;
}

.card-body {
  min-width: 0;
  display: flex;
  flex-direction: column;
  padding: 1.25rem 1.45rem 1.35rem;
}

.card-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.35rem 0.8rem;
  margin: 0 0 0.45rem;
  color: var(--teal);
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0.075em;
  line-height: 1.4;
  text-transform: uppercase;
}

.computational-card .card-meta { color: var(--blue); }
.lab-card h3 { margin-bottom: 0.55rem; font-size: clamp(1.25rem, 2vw, 1.5rem); }
.lab-card h3 + p { margin: 0; color: var(--ink-soft); font-size: 0.98rem; }

.topic-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.42rem;
  margin: 0.9rem 0 1.05rem;
  padding: 0;
  list-style: none;
}

.topic-list li {
  padding: 0.32rem 0.62rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--ink-soft);
  background: #f7fafc;
  font-size: 0.78rem;
  line-height: 1.25;
}

.primary-action {
  display: inline-flex;
  align-items: center;
  align-self: flex-start;
  gap: 0.5rem;
  padding: 0.68rem 0.92rem;
  border-radius: 8px;
  color: #fff;
  background: var(--navy);
  font-size: 0.9rem;
  font-weight: 760;
  text-decoration: none;
}

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

.card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-top: auto;
}

.module-count {
  margin-left: auto;
  color: var(--ink-soft);
  font-size: 0.8rem;
  font-weight: 750;
  text-align: right;
  white-space: nowrap;
}

.teaching-note {
  display: grid;
  grid-template-columns: minmax(220px, 0.6fr) 1fr;
  gap: 3rem;
  margin-top: 4.75rem;
  padding-top: 2.5rem;
  border-top: 1px solid var(--line-dark);
}

.teaching-note h2 { font-size: 1.6rem; }
.teaching-note p { margin: 0; color: var(--ink-soft); }

.site-footer {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 2rem;
  padding: 1.75rem 5vw;
  color: #dcebf3;
  background: var(--navy);
  font-size: 0.82rem;
}

.site-footer p { margin: 0; }
.site-footer a { color: #fff; font-weight: 700; text-decoration: none; }
.site-footer a:hover { text-decoration: underline; text-underline-offset: 0.2em; }
.footer-attribution { display: grid; gap: 0.45rem; max-width: 720px; }
.footer-disclaimer { color: #b9cedb; line-height: 1.5; }
.footer-links { flex: 0 0 auto; display: grid; gap: 0.45rem; text-align: right; }

@media (max-width: 860px) {
  main { width: min(100% - 2rem, 720px); }
  .lab-grid { grid-template-columns: 1fr; grid-auto-rows: auto; }
}

@media (max-width: 680px) {
  .site-header { align-items: flex-start; flex-direction: column; gap: 0.7rem; padding: 0.75rem 1rem; }
  .brand { font-size: 1rem; }
  .site-nav { width: 100%; }
  .site-nav a { padding: 0.44rem 0.68rem; }
  main { padding: 3.4rem 0; }
  h1 { font-size: clamp(2.15rem, 11vw, 3.1rem); }
  .collection-summary div { width: 100%; padding: 0.25rem 0; border-left: 0; }
  .section-heading { align-items: flex-start; flex-direction: column; gap: 0.25rem; }
  .lab-card { grid-template-columns: 1fr; }
  .card-band { justify-content: flex-start; min-height: 60px; padding: 0.65rem 1.2rem; }
  .card-body { padding: 1.3rem 1.25rem 1.4rem; }
  .card-footer { gap: 0.75rem; }
  .teaching-note { grid-template-columns: 1fr; gap: 0.5rem; }
  .site-footer { flex-direction: column; padding: 1.5rem 1rem; }
  .footer-links { text-align: left; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}