:root {
  color-scheme: light;
  --ink: #101820;
  --muted: #5f6b76;
  --faint: #87919b;
  --paper: #f7f9fb;
  --surface: #ffffff;
  --line: #d8e0e7;
  --blue: #0878bd;
  --blue-dark: #075985;
  --footer: #071622;
  --focus: #159eea;
  --max: 1120px;
  --header-height: 76px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--surface);
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  font-size: 16px;
  line-height: 1.65;
  letter-spacing: 0;
}

body.menu-open {
  overflow: hidden;
}

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

img {
  display: block;
}

button {
  font: inherit;
}

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

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 1000;
  transform: translateY(-140%);
  border-radius: 4px;
  background: var(--ink);
  color: #ffffff;
  padding: 10px 14px;
  transition: transform 180ms ease;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  min-height: var(--header-height);
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(18px);
}

.site-header.is-scrolled {
  box-shadow: 0 10px 30px rgba(16, 24, 32, 0.06);
}

.nav,
.section-shell,
.footer-shell {
  width: min(100% - 48px, var(--max));
  margin: 0 auto;
}

.nav {
  min-height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  min-height: 48px;
  flex: 0 0 auto;
}

.brand-logo {
  width: clamp(176px, 17vw, 220px);
  height: auto;
  max-height: 52px;
  object-fit: contain;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-links a {
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
  transition: color 180ms ease;
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--ink);
}

.menu-button {
  display: none;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface);
  color: var(--ink);
  cursor: pointer;
}

.menu-button span {
  width: 20px;
  height: 2px;
  background: currentColor;
  transition:
    transform 180ms ease,
    opacity 180ms ease;
}

.menu-button[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

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

.menu-button[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.hero {
  min-height: calc(100svh - var(--header-height));
  display: grid;
  align-items: center;
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}

.hero-layout {
  padding: 92px 0 110px;
}

.eyebrow,
.section-label {
  margin: 0 0 18px;
  color: var(--blue-dark);
  font-size: 12px;
  font-weight: 760;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1,
h2,
h3 {
  margin: 0;
  letter-spacing: 0;
}

h1 {
  max-width: 920px;
  font-size: clamp(52px, 8vw, 112px);
  line-height: 0.96;
  font-weight: 760;
}

h2 {
  max-width: 680px;
  font-size: clamp(34px, 4.7vw, 64px);
  line-height: 1.04;
  font-weight: 740;
}

h3 {
  font-size: 22px;
  line-height: 1.24;
  font-weight: 720;
}

.hero-lede {
  max-width: 760px;
  margin: 34px 0 0;
  color: var(--muted);
  font-size: clamp(19px, 2vw, 25px);
  line-height: 1.48;
}

.section {
  padding: 112px 0;
}

.about-section,
.team-section {
  background: var(--surface);
}

.research-section {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.split-layout,
.contact-layout {
  display: grid;
  grid-template-columns: minmax(280px, 0.78fr) minmax(0, 1fr);
  gap: 72px;
  align-items: start;
}

.body-copy {
  display: grid;
  gap: 22px;
}

.body-copy p,
.contact-card p,
.footer-shell p {
  margin: 0;
  color: var(--muted);
  font-size: 18px;
}

.section-heading {
  margin-bottom: 54px;
}

.principle-list {
  border-top: 1px solid var(--line);
}

.principle-item {
  display: grid;
  grid-template-columns: 82px minmax(0, 1fr);
  gap: 30px;
  padding: 34px 0;
  border-bottom: 1px solid var(--line);
}

.principle-item span {
  color: var(--blue);
  font-family:
    "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 14px;
  font-weight: 760;
}

.principle-item p {
  max-width: 760px;
  margin: 10px 0 0;
  color: var(--muted);
  font-size: 18px;
}

.contact-section {
  border-top: 1px solid var(--line);
  background: var(--surface);
}

.contact-card {
  display: grid;
  gap: 20px;
  align-content: start;
  border-left: 3px solid var(--blue);
  padding-left: 28px;
}

.contact-link {
  color: var(--ink);
  font-size: clamp(24px, 3.2vw, 38px);
  font-weight: 740;
  line-height: 1.12;
}

.contact-link:hover {
  color: var(--blue-dark);
}

.site-footer {
  background: var(--footer);
  color: rgba(226, 244, 255, 0.7);
}

.footer-shell {
  display: grid;
  grid-template-columns: minmax(0, 0.7fr) minmax(260px, 1fr);
  gap: 72px;
  align-items: start;
  padding: 46px 0 54px;
}

.footer-logo {
  width: 210px;
  height: auto;
}

.footer-shell p {
  color: rgba(226, 244, 255, 0.66);
  font-size: 15px;
}

@media (max-width: 880px) {
  :root {
    --header-height: 70px;
  }

  .nav,
  .section-shell,
  .footer-shell {
    width: min(100% - 32px, var(--max));
  }

  .menu-button {
    display: inline-flex;
  }

  .nav-links {
    position: fixed;
    top: var(--header-height);
    right: 0;
    left: 0;
    display: grid;
    gap: 0;
    padding: 8px 24px 20px;
    border-bottom: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.98);
    transform: translateY(-120%);
    transition: transform 220ms ease;
  }

  .nav-links.is-open {
    transform: translateY(0);
  }

  .nav-links a {
    min-height: 52px;
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--line);
  }

  .nav-links a:last-child {
    border-bottom: 0;
  }

  .hero {
    min-height: auto;
  }

  .hero-layout {
    padding: 78px 0 90px;
  }

  .section {
    padding: 78px 0;
  }

  .split-layout,
  .contact-layout,
  .footer-shell {
    grid-template-columns: 1fr;
    gap: 38px;
  }
}

@media (max-width: 620px) {
  .brand-logo {
    width: min(158px, 54vw);
  }

  h1 {
    font-size: 48px;
  }

  h2 {
    font-size: 34px;
  }

  .hero-lede,
  .body-copy p,
  .principle-item p,
  .contact-card p {
    font-size: 16px;
  }

  .principle-item {
    grid-template-columns: 1fr;
    gap: 10px;
    padding: 28px 0;
  }

  .contact-card {
    padding-left: 20px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}