:root {
  --ink: #17212b;
  --muted: #5d6875;
  --line: #d9e2ea;
  --paper: #fbfcfd;
  --white: #ffffff;
  --teal: #0c7c83;
  --teal-soft: #dff4f2;
  --coral: #c94d42;
  --coral-soft: #fde8e4;
  --gold: #b88712;
  --gold-soft: #fff1c7;
  --indigo: #4058a8;
  --shadow: 0 18px 50px rgba(23, 33, 43, 0.1);
  --radius: 8px;
  --max-width: 1160px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

a {
  color: inherit;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px clamp(20px, 4vw, 56px);
  background: rgba(251, 252, 253, 0.88);
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(18px);
  transition: border-color 180ms ease, box-shadow 180ms ease;
}

.site-header.is-scrolled {
  border-color: var(--line);
  box-shadow: 0 8px 28px rgba(23, 33, 43, 0.08);
}

.brand,
.site-nav,
.hero-actions,
.contact-actions,
.filter-group {
  display: flex;
  align-items: center;
}

.brand {
  gap: 10px;
  min-width: max-content;
  font-weight: 760;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  color: var(--white);
  background: var(--ink);
  border-radius: 50%;
  font-size: 0.82rem;
  letter-spacing: 0;
}

.site-nav {
  gap: clamp(12px, 2.4vw, 28px);
  color: var(--muted);
  font-size: 0.94rem;
}

.site-nav a {
  position: relative;
  text-decoration: none;
}

.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: -8px;
  left: 0;
  height: 2px;
  background: var(--teal);
  border-radius: 2px;
  content: "";
  opacity: 0;
  transform: scaleX(0.4);
  transition: opacity 180ms ease, transform 180ms ease;
}

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

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

.section,
.hero,
.site-footer {
  width: min(var(--max-width), calc(100% - 40px));
  margin: 0 auto;
}

.section {
  padding: 86px 0;
}

.section-band {
  width: 100%;
  max-width: none;
  padding-right: max(20px, calc((100vw - var(--max-width)) / 2));
  padding-left: max(20px, calc((100vw - var(--max-width)) / 2));
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(340px, 0.95fr);
  gap: clamp(36px, 6vw, 80px);
  align-items: center;
  min-height: calc(100vh - 70px);
  padding-top: 70px;
  padding-bottom: 82px;
  background:
    linear-gradient(135deg, rgba(12, 124, 131, 0.11), transparent 34%),
    linear-gradient(315deg, rgba(201, 77, 66, 0.1), transparent 36%),
    var(--paper);
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--teal);
  font-size: 0.78rem;
  font-weight: 780;
  letter-spacing: 0;
  text-transform: uppercase;
}

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

h1 {
  max-width: 780px;
  margin-bottom: 22px;
  font-size: clamp(2.65rem, 6.2vw, 5.55rem);
  line-height: 0.98;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 0;
  font-size: clamp(2rem, 4vw, 3.25rem);
  line-height: 1.08;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 12px;
  font-size: 1.16rem;
  line-height: 1.25;
  letter-spacing: 0;
}

.hero-lede {
  max-width: 660px;
  margin-bottom: 30px;
  color: var(--muted);
  font-size: clamp(1.04rem, 1.8vw, 1.24rem);
}

.hero-actions,
.contact-actions {
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  gap: 9px;
  padding: 12px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-weight: 760;
  text-decoration: none;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.button-dot {
  width: 9px;
  height: 9px;
  background: currentColor;
  border-radius: 50%;
}

.button-arrow {
  width: 12px;
  height: 12px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(-45deg);
}

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

.button.primary {
  color: var(--white);
  background: var(--ink);
  border-color: var(--ink);
}

.button.secondary {
  background: var(--white);
}

.button.secondary:hover {
  border-color: var(--teal);
}

.hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  max-width: 720px;
  margin: 38px 0 0;
}

.hero-facts div {
  padding: 16px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.hero-facts dt {
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 760;
  text-transform: uppercase;
}

.hero-facts dd {
  margin: 4px 0 0;
  font-weight: 760;
  line-height: 1.35;
}

.hero-visual {
  align-self: stretch;
  display: grid;
  min-height: 420px;
  place-items: center;
}

.hero-visual img {
  width: min(100%, 620px);
  filter: drop-shadow(0 28px 48px rgba(23, 33, 43, 0.18));
}

.section-heading {
  max-width: 780px;
  margin-bottom: 34px;
}

.compact-heading {
  display: flex;
  max-width: none;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
}

.research-grid,
.project-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.research-card,
.project-card,
.publication,
.timeline-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--white);
}

.research-card {
  min-height: 250px;
  padding: 26px;
  border-top-width: 5px;
  box-shadow: var(--shadow);
}

.research-card p,
.project-card p,
.timeline-item p,
.publication p {
  color: var(--muted);
}

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

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

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

.publication-band {
  background:
    linear-gradient(120deg, rgba(64, 88, 168, 0.1), transparent 32%),
    linear-gradient(300deg, rgba(184, 135, 18, 0.16), transparent 35%),
    #f6f9fb;
}

.publication {
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr);
  gap: 24px;
  max-width: 960px;
  padding: 30px;
}

.pub-year {
  display: grid;
  width: 92px;
  height: 92px;
  place-items: center;
  color: var(--white);
  background: var(--indigo);
  border-radius: 50%;
  font-size: 1.28rem;
  font-weight: 800;
}

.filter-group {
  gap: 6px;
  padding: 5px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.filter-button {
  min-height: 36px;
  padding: 7px 12px;
  color: var(--muted);
  background: transparent;
  border: 0;
  border-radius: 6px;
  cursor: pointer;
  font: inherit;
  font-weight: 760;
}

.filter-button.is-active {
  color: var(--white);
  background: var(--teal);
}

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

.project-card {
  padding: 26px;
  transition: opacity 180ms ease, transform 180ms ease;
}

.project-card.is-hidden {
  display: none;
}

.project-kicker,
.timeline-date {
  color: var(--coral);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.project-card ul {
  margin: 16px 0 0;
  padding-left: 20px;
  color: var(--muted);
}

.split-section {
  display: grid;
  grid-template-columns: 0.76fr 1.24fr;
  gap: clamp(30px, 6vw, 76px);
}

.timeline {
  display: grid;
  gap: 16px;
}

.timeline-item {
  position: relative;
  padding: 24px 24px 24px 32px;
}

.timeline-item::before {
  position: absolute;
  top: 24px;
  bottom: 24px;
  left: 0;
  width: 5px;
  background: var(--teal);
  border-radius: 0 4px 4px 0;
  content: "";
}

.skills-section {
  padding-top: 42px;
}

.skills-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.skills-list span {
  padding: 9px 13px;
  color: var(--ink);
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-weight: 720;
}

.contact-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) max-content;
  gap: 32px;
  align-items: center;
  margin-bottom: 44px;
  padding: 42px;
  color: var(--white);
  background: var(--ink);
  border-radius: var(--radius);
}

.contact-section .eyebrow,
.contact-section h2 {
  color: var(--white);
}

.contact-section .button.secondary {
  color: var(--ink);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 28px 0 42px;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  font-weight: 760;
  text-decoration: none;
}

@media (max-width: 900px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .site-nav {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 48px;
  }

  .hero-visual {
    min-height: 310px;
  }

  .research-grid,
  .project-grid,
  .split-section,
  .contact-section {
    grid-template-columns: 1fr;
  }

  .compact-heading {
    align-items: start;
    flex-direction: column;
  }

  .contact-section {
    padding: 30px;
  }

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

@media (max-width: 640px) {
  .section,
  .hero,
  .site-footer {
    width: min(100% - 28px, var(--max-width));
  }

  .section {
    padding: 62px 0;
  }

  .section-band {
    width: 100%;
    padding-right: 14px;
    padding-left: 14px;
  }

  h1 {
    font-size: 2.55rem;
  }

  .hero-facts,
  .publication {
    grid-template-columns: 1fr;
  }

  .publication {
    padding: 24px;
  }

  .pub-year {
    width: 76px;
    height: 76px;
    font-size: 1rem;
  }

  .filter-group {
    width: 100%;
    overflow-x: auto;
  }

  .button {
    width: 100%;
  }

  .site-footer {
    flex-direction: column;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}