:root {
  --navy: #102a43;
  --dark-navy: #0d2435;
  --teal: #147d92;
  --seafoam: #9fd8cb;
  --amber: #e6a23c;
  --lavender: #d9d6f0;
  --porcelain: #f5f8fa;
  --white: #ffffff;
  --text: #172b3a;
  --muted: #637381;
  --border: #d8e2e8;
  --radius-sm: 10px;
  --radius-md: 18px;
  --radius-lg: 34px;
  --shadow-sm: 0 10px 30px rgba(16, 42, 67, 0.08);
  --shadow-md: 0 24px 65px rgba(16, 42, 67, 0.14);
  --container: 1180px;
}

/* =========================
   Reset and base
   ========================= */
* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 82px;
}

body {
  margin: 0;
  color: var(--text);
  background: var(--white);
  font-family:
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Arial,
    sans-serif;
  line-height: 1.65;
  overflow-x: hidden;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  line-height: 1.08;
}

h1,
h2 {
  font-weight: 650;
  letter-spacing: -0.045em;
}

h1 {
  max-width: 820px;
  margin-bottom: 1.5rem;
  font-size: clamp(3.15rem, 6.4vw, 6.65rem);
}

h1 em {
  color: var(--teal);
  font-style: normal;
}

h2 {
  margin-bottom: 0;
  font-size: clamp(2.3rem, 4.4vw, 4.45rem);
}

h3 {
  font-size: 1.3rem;
}

a {
  color: inherit;
  text-decoration: none;
}

img,
svg {
  display: block;
  max-width: 100%;
}

button,
input {
  font: inherit;
}

.container {
  width: min(calc(100% - 2.5rem), var(--container));
  margin-inline: auto;
}

/* =========================
   Accessibility
   ========================= */
.skip-link {
  position: fixed;
  z-index: 100;
  top: 0.5rem;
  left: 0.5rem;
  padding: 0.7rem 1rem;
  color: var(--navy);
  background: var(--white);
  border-radius: var(--radius-sm);
  transform: translateY(-150%);
}

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

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  white-space: nowrap;
  border: 0;
  clip-path: inset(50%);
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--amber);
  outline-offset: 3px;
}

/* =========================
   Header and navigation
   ========================= */
.site-header {
  position: sticky;
  z-index: 40;
  top: 0;
  height: 82px;
  background: rgba(255, 253, 252, 0.95);
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(16px);
}

.site-header.scrolled {
  border-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.navigation {
  display: flex;
  align-items: center;
  height: 100%;
  gap: 1.8rem;
}

.brand {
  width: 220px;
  margin-right: auto;
}

nav {
  display: flex;
  gap: 1.45rem;
}

nav a {
  position: relative;
  padding-block: 0.35rem;
  font-size: 0.78rem;
  font-weight: 750;
}

nav a::after {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 2px;
  background: var(--teal);
  content: "";
  transform: scaleX(0);
  transition: 180ms ease;
}

nav a:hover::after,
nav a.active::after {
  transform: scaleX(1);
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.82rem 1.4rem;
  color: var(--white);
  background: var(--teal);
  border: 1px solid var(--teal);
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 850;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  transition: 180ms ease;
}

.button:hover {
  background: var(--navy);
  border-color: var(--navy);
  transform: translateY(-2px);
}

.menu-button {
  display: none;
  align-items: center;
  gap: 0.55rem;
  padding: 0.4rem;
  color: var(--navy);
  background: transparent;
  border: 0;
  font-size: 0.75rem;
  font-weight: 800;
}

.menu-icon i {
  display: block;
  width: 23px;
  height: 2px;
  margin: 4px;
  background: currentColor;
  transition: 180ms ease;
}

/* =========================
   Hero
   ========================= */
.hero {
  position: relative;
  padding: 6.7rem 0 7rem;
  background: var(--porcelain);
  overflow: hidden;
}

.hero::before {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(
    rgba(20, 125, 146, 0.17) 1px,
    transparent 1px
  );
  background-size: 28px 28px;
  content: "";
  mask-image: linear-gradient(to right, transparent 30%, #000);
}

.hero-layout {
  position: relative;
  display: grid;
  grid-template-columns: 1.3fr 0.7fr;
  align-items: center;
  gap: 4rem;
}

.eyebrow {
  margin-bottom: 1.1rem;
  color: var(--teal);
  font-size: 0.67rem;
  font-weight: 850;
  letter-spacing: 0.19em;
  text-transform: uppercase;
}

.lead {
  max-width: 720px;
  color: var(--muted);
  font-size: 1.15rem;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 1.7rem;
  margin-top: 2.2rem;
}

.secondary-link {
  color: var(--navy);
  font-size: 0.8rem;
  font-weight: 800;
}

.hero-visual {
  position: relative;
  min-width: 400px;
  aspect-ratio: 1;
}

.hero-visual > img {
  position: absolute;
  z-index: 4;
  width: 150px;
  inset: 50% auto auto 50%;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  transform: translate(-50%, -50%);
}

.orbit {
  position: absolute;
  border: 1px solid rgba(16, 42, 67, 0.2);
  border-radius: 50%;
}

.orbit-outer {
  inset: 7%;
}

.orbit-inner {
  inset: 24%;
  border-color: var(--teal);
  border-style: dashed;
}

.node {
  position: absolute;
  width: 11px;
  height: 11px;
  background: var(--amber);
  border-radius: 50%;
}

.node-one {
  top: 6%;
  left: 49%;
}

.node-two {
  top: 48%;
  right: 6%;
  background: var(--teal);
}

.node-three {
  bottom: 7%;
  left: 48%;
  background: var(--lavender);
}

.floating-label {
  position: absolute;
  z-index: 5;
  padding: 0.48rem 0.72rem;
  color: var(--white);
  background: var(--navy);
  border-radius: var(--radius-sm);
  font-size: 0.64rem;
  font-weight: 850;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.label-language {
  top: 1%;
  left: 30%;
}

.label-networks {
  top: 35%;
  right: -3%;
  background: var(--teal);
}

.label-evidence {
  right: 3%;
  bottom: 12%;
  color: var(--navy);
  background: var(--amber);
}

.label-systems {
  bottom: 3%;
  left: 25%;
  color: var(--navy);
  background: var(--seafoam);
}

.label-inquiry {
  top: 40%;
  left: -4%;
  background: var(--slate, #64748b);
}

/* =========================
   Introduction band
   ========================= */
.habits {
  color: var(--white);
  background: var(--dark-navy);
}

.habits-layout {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  padding-block: 1.35rem;
}

.habits-layout p {
  margin: 0;
  color: var(--seafoam);
  font-size: 0.69rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.habits-layout div {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  font-size: 0.69rem;
  font-weight: 750;
  text-transform: uppercase;
}

.habits-layout i {
  color: var(--amber);
  font-style: normal;
}

/* =========================
   Shared section headings
   ========================= */
.section {
  padding: 6.6rem 0;
}

.section-heading,
.notebook-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 3.75rem;
  margin-bottom: 3rem;
}

.section-heading > div,
.notebook-heading > div {
  max-width: 790px;
}

.section-heading > p {
  max-width: 390px;
  margin: 0;
  color: var(--muted);
}

/* =========================
   Learning domains
   ========================= */
.domains {
  background: var(--white);
}

.domains-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.domain-card {
  display: flex;
  flex-direction: column;
  padding: 1.7rem;
  background: var(--porcelain);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: 200ms ease;
}

.domain-card:hover {
  background: var(--white);
  border-color: var(--teal);
  box-shadow: var(--shadow-md);
  transform: translateY(-5px);
}

.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-top span {
  color: var(--amber);
  font-size: 0.7rem;
  font-weight: 850;
}

.card-top svg {
  width: 48px;
  height: 48px;
  fill: var(--seafoam);
  stroke: var(--teal);
  stroke-width: 3;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.domain-card h3 {
  min-height: 58px;
  margin: 2.5rem 0 1rem;
  color: var(--navy);
  font-size: 1.5rem;
}

.domain-card > p {
  min-height: 140px;
  color: var(--muted);
  font-size: 0.81rem;
}

.domain-card ul {
  padding: 1rem 0 0;
  margin: auto 0 0;
  border-top: 1px solid var(--border);
  list-style: none;
}

.domain-card li {
  margin-block: 0.4rem;
  font-size: 0.7rem;
}

.domain-card li::before {
  margin-right: 0.45rem;
  color: var(--teal);
  content: "—";
}

/* =========================
   Cross-discipline connections
   ========================= */
.connections {
  background: #eef7f5;
}

.connections-heading {
  max-width: 800px;
  margin-bottom: 3rem;
}

.connection-list {
  border-top: 1px solid var(--teal);
}

.connection-list div {
  display: grid;
  grid-template-columns: 1fr 70px 1fr;
  align-items: center;
  padding-block: 1.45rem;
  border-bottom: 1px solid var(--border);
  font-size: clamp(1.35rem, 3vw, 2.6rem);
  letter-spacing: -0.03em;
  text-transform: uppercase;
}

.connection-list strong:last-child {
  color: var(--teal);
  text-align: right;
}

.connection-list span {
  color: var(--amber);
  text-align: center;
}

.connection-note {
  max-width: 650px;
  margin: 1.5rem 0 0 auto;
  color: var(--muted);
}

/* =========================
   Method
   ========================= */
.method {
  color: #cbd8e0;
  background: var(--navy);
}

.inverse h2,
.method h3 {
  color: var(--white);
}

.inverse .eyebrow {
  color: var(--seafoam);
}

.method-grid {
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
}

.method-grid::before {
  position: absolute;
  top: 2rem;
  right: 8%;
  left: 8%;
  height: 2px;
  background: rgba(159, 216, 203, 0.45);
  content: "";
}

.method-step {
  position: relative;
  z-index: 1;
  padding: 1rem 1.4rem 1.5rem;
}

.method-step span {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  color: var(--navy);
  background: var(--seafoam);
  border: 6px solid var(--navy);
  border-radius: 50%;
  font-size: 0.64rem;
  font-weight: 850;
}

.method-step h3 {
  margin: 2.4rem 0 0.8rem;
}

.method-step p {
  color: #9fb4c0;
  font-size: 0.79rem;
}

/* =========================
   Perspectives and profiles
   ========================= */
.perspectives {
  background: var(--porcelain);
}

.profiles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.profile {
  display: flex;
  flex-direction: column;
  padding: 1.2rem 1.2rem 1.6rem;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
}

.avatar {
  position: relative;
  display: grid;
  place-items: center;
  aspect-ratio: 1.5;
  color: var(--seafoam);
  background: var(--navy);
  border-radius: var(--radius-sm);
  font-size: 3.8rem;
  font-weight: 750;
  letter-spacing: -0.07em;
  overflow: hidden;
}

.avatar::before {
  position: absolute;
  width: 180px;
  height: 180px;
  border: 1px dashed rgba(159, 216, 203, 0.6);
  border-radius: 50%;
  content: "";
}

.reference .avatar {
  color: var(--lavender);
}

.avatar-wide {
  font-size: 3.1rem;
}

.avatar span {
  position: absolute;
  right: 0.85rem;
  bottom: 0.65rem;
  font-size: 0.62rem;
  letter-spacing: 0.1em;
}

.area {
  margin: 1.4rem 0 0.55rem;
  color: var(--teal);
  font-size: 0.63rem;
  font-weight: 850;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.profile h3 {
  margin-bottom: 0.75rem;
  color: var(--navy);
  font-size: 1.5rem;
}

.profile > p:not(.area) {
  min-height: 105px;
  color: var(--muted);
  font-size: 0.79rem;
}

.contact,
.reference-label {
  padding-top: 0.9rem;
  margin-top: auto;
  border-top: 1px solid var(--border);
}

.contact > span,
.reference-label {
  color: var(--muted);
  font-size: 0.68rem;
}

.contact a {
  display: block;
  margin: 0.2rem 0 0.65rem;
  color: var(--navy);
  font-size: 0.72rem;
  font-weight: 750;
  overflow-wrap: anywhere;
}

.copy-button {
  padding: 0.45rem 0.7rem;
  color: var(--teal);
  background: transparent;
  border: 1px solid var(--teal);
  border-radius: 999px;
  cursor: pointer;
  font-size: 0.67rem;
  font-weight: 800;
}

.copy-button:hover {
  color: var(--white);
  background: var(--teal);
}

.independence-note {
  padding: 1.5rem;
  margin-top: 1.5rem;
  background: #fff8e9;
  border-left: 5px solid var(--amber);
  border-radius: var(--radius-sm);
}

.independence-note h3 {
  margin-bottom: 0.55rem;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.independence-note p {
  margin: 0.35rem 0;
  color: #5b6670;
  font-size: 0.76rem;
}

/* =========================
   Research notebook
   ========================= */
.notebook {
  background: var(--white);
}

.notebook-heading > div > p:last-child {
  max-width: 620px;
  margin: 1rem 0 0;
  color: var(--muted);
}

.notebook-tools {
  width: min(100%, 400px);
}

.search {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  padding-inline: 1rem;
  background: var(--porcelain);
  border: 1px solid var(--border);
  border-radius: 999px;
}

.search input {
  width: 100%;
  padding-block: 0.88rem;
  background: transparent;
  border: 0;
  outline: 0;
}

.result-count {
  margin: 0.55rem 1rem 0;
  color: var(--muted);
  font-size: 0.68rem;
}

.notes-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.notes-list details {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.notes-list summary {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 1.15rem;
  cursor: pointer;
  list-style: none;
  font-weight: 750;
}

.notes-list summary span {
  display: flex;
  gap: 0.65rem;
}

.notes-list summary b {
  color: var(--amber);
}

.notes-list summary em {
  padding: 0.25rem 0.5rem;
  margin-left: auto;
  color: var(--teal);
  background: #e9f5f2;
  border-radius: 999px;
  font-size: 0.62rem;
  font-style: normal;
  text-transform: uppercase;
}

.notes-list summary i {
  font-size: 1.2rem;
  font-style: normal;
  transition: 180ms ease;
}

.notes-list details[open] summary i {
  transform: rotate(45deg);
}

.notes-list details p {
  padding: 0 1.25rem 1.25rem 3.2rem;
  margin: 0;
  color: var(--muted);
  font-size: 0.82rem;
}

.empty-state {
  padding: 1.2rem;
  text-align: center;
  background: var(--porcelain);
}

/* =========================
   About
   ========================= */
.about {
  background: var(--lavender);
}

.about-layout {
  display: grid;
  grid-template-columns: 0.65fr 1fr;
  align-items: center;
  gap: 5.5rem;
}

.about-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 2.4rem;
  color: var(--white);
  background: var(--dark-navy);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  text-align: center;
}

.about-panel img {
  width: 190px;
  margin-bottom: 1.5rem;
  border-radius: var(--radius-lg);
}

.about-panel span,
.about-panel strong {
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.about-panel i {
  margin-block: 0.55rem;
  color: var(--amber);
  font-style: normal;
}

.about-copy p {
  color: #505f70;
}

.values {
  padding: 1.1rem 1.3rem;
  margin: 1.5rem 0;
  background: rgba(255, 255, 255, 0.55);
  border-radius: var(--radius-sm);
}

.values h3 {
  margin-bottom: 0.7rem;
  font-size: 0.8rem;
  text-transform: uppercase;
}

.values ul {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.35rem 1rem;
  padding: 0;
  margin: 0;
  list-style: none;
  font-size: 0.75rem;
}

.values li::before {
  margin-right: 0.45rem;
  color: var(--teal);
  content: "•";
}

/* =========================
   Final call to action
   ========================= */
.final-cta {
  color: var(--white);
  background: var(--teal);
}

.cta-layout {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 4rem;
}

.cta-layout > div {
  max-width: 830px;
}

.final-cta .eyebrow {
  color: var(--dark-navy);
}

.final-cta h2 {
  color: var(--white);
}

.final-cta p {
  max-width: 660px;
  margin-top: 1.2rem;
  color: #dcf2ee;
}

.cta-button {
  flex: 0 0 auto;
  color: var(--navy);
  background: var(--white);
  border-color: var(--white);
}

/* =========================
   Footer
   ========================= */
footer {
  padding: 4rem 0 1.2rem;
  color: #adc0ca;
  background: var(--dark-navy);
}

.footer-layout {
  display: grid;
  grid-template-columns: 2fr 1fr auto;
  align-items: start;
  gap: 4rem;
}

.footer-layout > div > img {
  width: 235px;
  padding: 0.35rem;
  background: var(--white);
  border-radius: var(--radius-sm);
}

.footer-layout p,
.footer-nav a {
  font-size: 0.76rem;
}

.footer-nav {
  display: grid;
  gap: 0.45rem;
}

.footer-mark {
  width: 75px;
  border-radius: var(--radius-md);
}

.copyright {
  padding-top: 1.2rem;
  margin-top: 2.7rem;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  font-size: 0.68rem;
}

/* =========================
   Back to top and reveals
   ========================= */
.back-to-top {
  position: fixed;
  z-index: 20;
  right: 1.25rem;
  bottom: 1.25rem;
  width: 44px;
  height: 44px;
  color: var(--navy);
  background: var(--amber);
  border: 0;
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: 180ms ease;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: 600ms ease;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

[hidden] {
  display: none !important;
}

/* =========================
   Responsive: tablet
   ========================= */
@media (max-width: 1000px) {
  nav {
    gap: 0.75rem;
  }

  .header-action {
    display: none;
  }

  .domains-grid,
  .profiles-grid {
    grid-template-columns: 1fr 1fr;
  }

  .method-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
  }

  .method-grid::before {
    display: none;
  }

  .method-step {
    border-top: 2px solid var(--seafoam);
    background: rgba(255, 255, 255, 0.04);
  }
}

/* =========================
   Responsive: mobile
   ========================= */
@media (max-width: 760px) {
  .site-header {
    height: 70px;
  }

  .brand {
    width: 195px;
  }

  .menu-button {
    display: flex;
  }

  .menu-button[aria-expanded="true"] .menu-icon i:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
  }

  .menu-button[aria-expanded="true"] .menu-icon i:nth-child(2) {
    opacity: 0;
  }

  .menu-button[aria-expanded="true"] .menu-icon i:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
  }

  #primary-navigation {
    position: fixed;
    z-index: -1;
    top: 70px;
    right: 0;
    left: 0;
    display: flex;
    flex-direction: column;
    padding: 1rem 1.5rem 1.5rem;
    background: var(--white);
    border-bottom: 1px solid var(--border);
    transform: translateY(-130%);
    transition: 220ms ease;
  }

  #primary-navigation.open {
    transform: translateY(0);
  }

  #primary-navigation a {
    padding: 0.45rem;
  }

  .hero,
  .section {
    padding: 4.5rem 0;
  }

  .hero-layout,
  .domains-grid,
  .profiles-grid,
  .notes-list,
  .about-layout {
    grid-template-columns: 1fr;
  }

  .hero-visual {
    min-width: 0;
  }

  .hero-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .habits-layout {
    align-items: flex-start;
    flex-direction: column;
  }

  .habits-layout div {
    flex-wrap: wrap;
  }

  .section-heading,
  .notebook-heading {
    display: block;
  }

  .section-heading > p {
    margin-top: 1.2rem;
  }

  .method-grid {
    grid-template-columns: 1fr;
  }

  .domain-card h3,
  .domain-card > p,
  .profile > p:not(.area) {
    min-height: 0;
  }

  .notebook-tools {
    margin-top: 1.5rem;
  }

  .about-layout {
    gap: 3rem;
  }

  .cta-layout {
    align-items: stretch;
    flex-direction: column;
  }

  .footer-layout {
    grid-template-columns: 1fr 1fr;
  }

  .footer-mark {
    display: none;
  }
}

@media (max-width: 540px) {
  .container {
    width: min(calc(100% - 1.5rem), var(--container));
  }

  h1 {
    font-size: clamp(2.8rem, 14vw, 4.3rem);
  }

  .hero-visual {
    aspect-ratio: 1.12;
  }

  .floating-label {
    font-size: 0.58rem;
  }

  .connection-list div {
    grid-template-columns: 1fr 36px 1fr;
    font-size: 1rem;
  }

  .notes-list summary em {
    display: none;
  }

  .values ul,
  .footer-layout {
    grid-template-columns: 1fr;
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

.clipboard-helper {
  position: fixed;
  top: 0;
  left: 0;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}