:root {
  --ink: #18211f;
  --muted: #5c6863;
  --line: #d9e1de;
  --paper: #ffffff;
  --soft: #f6f8f7;
  --teal: #0f766e;
  --teal-dark: #0a4f4b;
  --coral: #d85645;
  --green: #357a52;
  --gold: #a86f16;
  --shadow: 0 18px 46px rgba(24, 33, 31, 0.13);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

section[id] {
  scroll-margin-top: 82px;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
}

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

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

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

p {
  color: var(--muted);
}

.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  padding: 0 32px;
  color: #ffffff;
  background: rgba(16, 25, 23, 0.78);
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  backdrop-filter: blur(14px);
}

.brand {
  font-weight: 800;
  font-size: 18px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  font-size: 14px;
  font-weight: 700;
}

.site-nav a {
  color: rgba(255, 255, 255, 0.82);
}

.site-nav a:hover,
.site-nav a.active {
  color: #ffffff;
}

.nav-toggle {
  display: none;
  width: 40px;
  height: 40px;
  padding: 9px;
  border: 1px solid rgba(255, 255, 255, 0.34);
  border-radius: 8px;
  background: transparent;
}

.nav-toggle span {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: #ffffff;
}

.hero {
  position: relative;
  min-height: 74vh;
  padding: 140px 32px 56px;
  color: #ffffff;
  background-image: url("assets/ot-bridge-overview.png");
  background-size: cover;
  background-position: center;
  isolation: isolate;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: -1;
  background: rgba(11, 20, 18, 0.74);
}

.hero-content {
  max-width: 1120px;
  margin: 0 auto;
}

.eyebrow,
.section-kicker {
  margin-bottom: 12px;
  color: var(--teal);
  font-size: 13px;
  font-weight: 800;
  text-transform: uppercase;
}

.hero .eyebrow {
  color: #a7f3d0;
}

h1 {
  margin-bottom: 22px;
  font-size: 64px;
  line-height: 1.02;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 18px;
  font-size: 36px;
  line-height: 1.18;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 10px;
  font-size: 20px;
  line-height: 1.25;
  letter-spacing: 0;
}

.hero-copy {
  max-width: 820px;
  color: rgba(255, 255, 255, 0.86);
  font-size: 21px;
}

.hero-links,
.pub-links,
.contact-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 10px 16px;
  border: 1px solid rgba(255, 255, 255, 0.32);
  border-radius: 8px;
  color: #ffffff;
  font-weight: 800;
  line-height: 1.2;
  overflow-wrap: anywhere;
}

.btn.primary {
  border-color: var(--teal);
  background: var(--teal);
}

.btn:hover {
  transform: translateY(-1px);
}

.quick-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  max-width: 980px;
  margin: 42px 0 0;
}

.quick-facts div {
  min-height: 112px;
  padding: 18px;
  border-left: 4px solid #a7f3d0;
  background: rgba(255, 255, 255, 0.1);
}

.quick-facts dt {
  margin-bottom: 6px;
  font-weight: 900;
}

.quick-facts dd {
  margin: 0;
  color: rgba(255, 255, 255, 0.78);
}

.band {
  padding: 92px 32px;
  background: var(--paper);
}

.band.light {
  background: var(--soft);
}

.news-band {
  padding-top: 54px;
  padding-bottom: 54px;
  border-bottom: 1px solid var(--line);
}

.section-inner {
  max-width: 1120px;
  margin: 0 auto;
}

.section-inner.compact {
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap: 42px;
  align-items: start;
}

.section-heading {
  max-width: 720px;
  margin-bottom: 34px;
}

.section-heading.wide {
  max-width: 820px;
}

.news-list {
  display: grid;
  gap: 16px;
}

.news-list article {
  display: grid;
  grid-template-columns: 104px minmax(0, 1fr);
  gap: 18px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.news-list time {
  color: var(--coral);
  font-weight: 900;
}

.news-list p,
.project-body p,
.publication p,
.timeline p,
.side-panel p {
  margin-bottom: 0;
}

.focus-grid,
.project-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.focus-card,
.publication,
.project-card,
.side-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--paper);
  box-shadow: 0 1px 0 rgba(24, 33, 31, 0.04);
}

.focus-card {
  min-height: 230px;
  padding: 24px;
  border-top-width: 5px;
}

.accent-teal {
  border-top-color: var(--teal);
}

.accent-coral {
  border-top-color: var(--coral);
}

.accent-green {
  border-top-color: var(--green);
}

.accent-gold {
  border-top-color: var(--gold);
}

.publication-list {
  display: grid;
  gap: 18px;
}

.publication {
  padding: 28px;
}

.publication.featured {
  border-left: 5px solid var(--teal);
  box-shadow: var(--shadow);
}

.pub-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 14px;
}

.pub-meta span,
.project-label {
  color: var(--teal-dark);
  font-size: 12px;
  font-weight: 900;
  text-transform: uppercase;
}

.authors {
  font-size: 15px;
}

.pub-links {
  margin-top: 18px;
}

.pub-links a {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--teal-dark);
  font-size: 14px;
  font-weight: 900;
}

.pub-links a:hover {
  border-color: var(--teal);
  background: #e8f5f2;
}

.project-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.project-card {
  overflow: hidden;
}

.project-card img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: #e8efed;
  border-bottom: 1px solid var(--line);
}

.project-body {
  padding: 22px;
}

.project-label {
  margin-bottom: 8px;
}

.two-column {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(300px, 0.7fr);
  gap: 34px;
}

.timeline {
  border-left: 3px solid var(--line);
}

.timeline article {
  position: relative;
  padding: 0 0 30px 28px;
}

.timeline article::before {
  content: "";
  position: absolute;
  top: 4px;
  left: -9px;
  width: 15px;
  height: 15px;
  border: 3px solid var(--teal);
  border-radius: 50%;
  background: var(--paper);
}

.timeline time {
  display: block;
  margin-bottom: 8px;
  color: var(--coral);
  font-size: 13px;
  font-weight: 900;
}

.side-panel {
  align-self: start;
  padding: 26px;
}

.side-panel section + section {
  margin-top: 26px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

.contact-band {
  padding: 74px 32px;
  color: #ffffff;
  background: #14201d;
}

.contact-band p {
  color: rgba(255, 255, 255, 0.78);
}

.contact-band .section-kicker {
  color: #a7f3d0;
}

.contact-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 32px;
  align-items: center;
}

.contact-actions {
  justify-content: flex-end;
}

.site-footer {
  padding: 28px 32px;
  text-align: center;
  background: #101816;
}

.site-footer p {
  margin: 0;
  color: rgba(255, 255, 255, 0.62);
  font-size: 14px;
}

@media (max-width: 980px) {
  .focus-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .section-inner.compact,
  .two-column,
  .contact-inner {
    grid-template-columns: 1fr;
  }

  .contact-actions {
    justify-content: flex-start;
  }
}

@media (max-width: 760px) {
  .site-header {
    padding: 0 18px;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: 68px;
    right: 18px;
    left: 18px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 8px;
    background: rgba(16, 25, 23, 0.96);
  }

  .site-nav.open {
    display: flex;
  }

  .site-nav a {
    padding: 12px;
  }

  .hero {
    min-height: 78vh;
    padding: 116px 20px 42px;
  }

  h1 {
    font-size: 42px;
  }

  h2 {
    font-size: 29px;
  }

  .hero-copy {
    font-size: 18px;
  }

  .quick-facts,
  .focus-grid,
  .project-grid {
    grid-template-columns: 1fr;
  }

  .quick-facts {
    display: none;
  }

  .band {
    padding: 68px 20px;
  }

  .news-band {
    padding-top: 42px;
    padding-bottom: 42px;
  }

  .news-list article {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .publication {
    padding: 22px;
  }
}

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

  .btn:hover {
    transform: none;
  }
}