:root {
  --bg: #ffffff;
  --surface: #f7f9fc;
  --surface-2: #eef3f8;
  --text: #14202b;
  --muted: #5f7284;
  --line: rgba(20, 32, 43, 0.1);
  --accent: #0d6e6e;
  --accent: #0d6e3a;
  --accent-2: #16ab5c; 
  --shadow: 0 18px 50px rgba(18, 35, 53, 0.08);
  --radius: 22px;
  --radius-sm: 14px;
  --max-width: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

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

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

.zsl-logo img {
  height: 50px;
}

iframe {
  width: 100%;
  min-height: 480px;
  border: 0;
  border-radius: 18px;
  background: #fff;
}

.container {
  width: min(calc(100% - 2rem), var(--max-width));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(20, 32, 43, 0.06);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 76px;
}

.brand {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.brand-mark {
  font-family: 'Poppins', 'Inter', sans-serif;
  font-size: 3rem;
  font-weight: 900;
  letter-spacing: -0.03em;
}

.brand-sub {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 10px;
}

.nav-toggle {
  display: none;
  border: 1px solid var(--line);
  background: white;
  border-radius: 12px;
  padding: 0.65rem 0.85rem;
  font: inherit;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.site-nav a {
  padding: 0.75rem 1rem;
  border-radius: 999px;
  color: var(--muted);
  font-weight: 500;
}

.site-nav a:hover,
.site-nav a[aria-current='page'] {
  color: var(--text);
  background: var(--surface);
}

.hero {
  padding: 4.5rem 0 3rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 2rem;
  align-items: stretch;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 0.8rem;
  border-radius: 999px;
  background: var(--surface);
  color: var(--accent);
  font-weight: 600;
  font-size: 0.92rem;
}

.hero h1,
.page-intro h1 {
  margin: 1rem 0 1rem;
  font-family: 'Poppins', 'Inter', sans-serif;
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  line-height: 1.02;
  letter-spacing: -0.05em;
}

.hero p,
.page-intro p {
  font-size: 1.08rem;
  color: var(--muted);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-top: 1.75rem;
}

.button,
.button-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: 0.95rem 1.25rem;
  border-radius: 999px;
  font-weight: 600;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.button {
  background: #008C46;
  color: white;
  box-shadow: 0 10px 28px rgba(13, 110, 58, 0.18);
}

.button-secondary {
  background: white;
  border: 1px solid var(--line);
}

.button:hover,
.button-secondary:hover {
  transform: translateY(-1px);
}

.hero-card,
.panel,
.card,
.quote-card,
.photo-card {
  background: white;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.hero-card {
  overflow: hidden;
  min-height: 100%;
}

.hero-image {
  aspect-ratio: 4 / 5;
  background: linear-gradient(135deg, rgba(13, 110, 58, 0.12), rgba(22, 171, 92, 0.2));
  position: relative;
}

.hero-image img,
.photo-slot img,
.person-photo img,
.research-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.photo-label {
  position: absolute;
  left: 1rem;
  bottom: 1rem;
  padding: 0.55rem 0.8rem;
  border: 0.5px solid grey;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  font-size: 0.9rem;
  color: var(--muted);
}

.hero-meta {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--line);
}

.hero-meta div {
  background: white;
  padding: 1rem;
}

.hero-meta strong,
.stat strong {
  display: block;
  font-family: 'Poppins', 'Inter', sans-serif;
  font-size: 1.35rem;
}

.hero-meta span,
.stat span,
.meta-note {
  color: var(--muted);
  font-size: 0.92rem;
}

section {
  padding: 1.5rem 0 4rem;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.4rem;
}

.section-heading h2 {
  margin: 0;
  font-family: 'Poppins', 'Inter', sans-serif;
  font-size: clamp(1.6rem, 2.2vw, 2.4rem);
  letter-spacing: -0.04em;
}

.section-heading p {
  margin: 0;
  color: var(--muted);
  max-width: 58ch;
}

.grid-3,
.grid-2,
.people-grid,
.pub-grid,
.research-grid,
.photo-grid,
.metrics-grid {
  display: grid;
  gap: 1.2rem;
}

.grid-3,
.people-grid,
.pub-grid,
.photo-grid,
.metrics-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

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

.card,
.panel,
.quote-card,
.photo-card {
  padding: 1.35rem;
}

.card h3,
.panel h3,
.person-card h3,
.research-card h3,
.pub-card h3 {
  margin-top: 0;
  margin-bottom: 0.55rem;
  font-size: 1.15rem;
}

.card h4,
.panel h4,
.person-card h4,
.research-card h4,
.pub-card h4 {
  margin-top: 0;
  margin-bottom: 0.55rem;
  font-size: 1.05rem;
}

.card p,
.panel p,
.person-card p,
.research-card p,
.pub-card p,
.timeline p,
.list-plain li {
  color: var(--muted);
}

.research-card {
  scroll-margin-top: 100px;
}

.card-link {
  display: block;
  text-decoration: none;
  color: inherit;
}

.card-link:hover {
  transform: translateY(-2px);
}

.card-link h3,
.card-link p {
  color: inherit;
}

.icon-badge {
  width: 2.5rem;
  height: 2.5rem;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: var(--surface);
  margin-bottom: 0.9rem;
  font-weight: 700;
  color: var(--accent);
}

.photo-slot,
.person-photo,
.research-image {
  overflow: hidden;
  border-radius: calc(var(--radius) - 6px);
  background: linear-gradient(135deg, rgba(13, 110, 58, 0.12), rgba(22, 171, 92, 0.22));
  aspect-ratio: 4 / 3;
  position: relative;
}

.person-card,
.research-card,
.pub-card {
  background: white;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.person-body,
.research-body,
.pub-body {
  padding: 1.25rem;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin-top: 1rem;
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.7rem;
  border-radius: 999px;
  background: var(--surface);
  color: var(--muted);
  font-size: 0.9rem;
}

.list-plain {
  list-style: none;
  padding: 0;
  margin: 0;
}

.list-plain li + li {
  margin-top: 0.8rem;
}

.timeline {
  border-left: 1px solid var(--line);
  padding-left: 1rem;
  margin-left: 0.2rem;
}

.timeline-item + .timeline-item {
  margin-top: 1.2rem;
}

.timeline-item strong,
.pub-meta strong {
  display: block;
  margin-bottom: 0.2rem;
}

.iframe-shell {
  padding: 1rem;
  background: var(--surface);
  border-radius: var(--radius);
  border: 1px solid var(--line);
}

.iframe-note {
  margin-top: 0.75rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.metrics-grid .stat {
  padding: 1.2rem;
  border-radius: 18px;
  background: var(--surface);
}

.page-intro {
  padding: 3.5rem 0 1.5rem;
}

.page-intro .eyebrow {
  margin-bottom: 0.25rem;
}

/* Publications page-intro two-column: text left, research profile right */
.page-intro-wrap {
  display: flex;
  align-items: flex-start;
  gap: 2rem;
}

.page-intro-content {
  flex: 1;
}

.page-intro-aside {
  flex-shrink: 0;
  width: 280px;
}

.research-intro,
.people-intro {
  padding: 1.5rem 0 1rem;
}

.publications-intro {
  padding: 1.5rem 0 1rem;
}

.publications-intro h1 {
  font-size: 2rem;
  margin: 0.5rem 0;
}

.publications-intro p {
  font-size: 1rem;
  line-height: 1.55;
  max-width: 75ch;
}

/* Two-column publications layout: main list left, sidebar right */
.publication-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 2rem;
  align-items: start;
}

.bibliography-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
}

.bibliography-header h2 {
  margin: 0;
  font-family: 'Poppins', 'Inter', sans-serif;
  font-size: clamp(1.4rem, 2vw, 2rem);
  letter-spacing: -0.03em;
}

.bibliography-header p {
  margin: 0.25rem 0 0;
  color: var(--muted);
}

.publication-list {
  padding-left: 1.5rem;
  margin: 0;
}

.publication-list li {
  color: var(--muted);
  padding: 0.55rem 0;
  border-bottom: 1px solid var(--line);
}

.publication-list li:last-child {
  border-bottom: none;
}

.sidebar-stack {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.metrics-grid-compact {
  grid-template-columns: repeat(2, 1fr);
}

.small-button {
  padding: 0.55rem 0.9rem;
  font-size: 0.9rem;
}

.profile-link {
  margin-top: 0.75rem;
  font-size: 0.95rem;
}

.split-layout {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 1.25rem;
}

.callout {
  padding: 1.25rem;
  border-radius: 18px;
  background: linear-gradient(135deg, rgba(13, 110, 58, 0.08), rgba(22, 171, 92, 0.14));
  border: 1px solid rgba(13, 110, 110, 0.12);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
  padding-block: 2rem;
  border-top: 1px solid var(--line);
}

.about-why h2 {
  margin: 0.5rem 0 1rem;
  font-family: 'Poppins', 'Inter', sans-serif;
  font-size: clamp(1.4rem, 2vw, 2rem);
  letter-spacing: -0.03em;
}

.about-why p {
  color: var(--muted);
  margin-bottom: 0.85rem;
}

.about-me-header {
  margin-bottom: 1rem;
}

.about-me-portrait {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  object-position: top;
  border: 1px solid var(--line);

  float: left;
  margin: 0 1.25rem 0.75rem 0;
}

.about-me p {
  color: var(--muted);
  margin-bottom: 0.85rem;
}

@media (max-width: 920px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

.footer {
  padding: 2rem 0 3.5rem;
  color: var(--muted);
}

.footer-wrap {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: center;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
}

.footer-links {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

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

.research-pubs {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.research-pubs h4 {
  margin: 0 0 0.5rem;
  font-size: 0.95rem;
}

.research-pubs ul {
  margin: 0;
  padding-left: 1.1rem;
}

.research-pubs li {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.45;
  margin-bottom: 0.45rem;
}

@media (max-width: 920px) {
  .hero-grid,
  .grid-3,
  .grid-2,
  .people-grid,
  .pub-grid,
  .research-grid,
  .photo-grid,
  .metrics-grid,
  .split-layout,
  .publication-layout {
    grid-template-columns: 1fr;
  }

  .hero-meta {
    grid-template-columns: 1fr;
  }

  .page-intro-wrap {
    flex-direction: column;
  }

  .page-intro-aside {
    width: 100%;
  }
}


@media (max-width: 760px) {
  .site-header {
    padding: 0.75rem 1rem;
  }

   .nav-wrap {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
  }


  .brand {
    order: 1;
    flex: 1 1 auto;
  }

  .zsl-logo {
    order: 2;
    margin-left: auto;
  }

  .nav-toggle {
    display: none;
  }

  .site-nav {
    order: 3;
    display: flex;
    position: static;
    width: 100%;
    margin-top: 0.5rem;
    flex-wrap: wrap;
    justify-content: flex-start;
  }

  .site-nav a {
    padding: 0.4rem 0.7rem;
    font-size: 0.9rem;
  }

  .zsl-logo img {
    height: 15px;
  }


  .brand-mark {
    font-size: 1.6rem;
  }

  .brand-sub {
    display: none;
  }

  .hero {
    padding: 2rem 0 1.5rem;
  }

  .hero-grid {
    gap: 1.5rem;
  }

  .hero h1 {
    font-size: 2rem;
    line-height: 1.05;
  }

  .hero .lead {
    font-size: 1rem;
    line-height: 1.45;
  }

  .hero-actions {
    margin-top: 1.2rem;
  }

  .hero-image img,
  .featured-image img {
    max-height: 260px;
    object-fit: cover;
  }

  .section-heading,
  .footer-wrap {
    flex-direction: column;
    align-items: start;
  }
}