:root {
  --bg: #f7fafb;
  --surface: #ffffff;
  --surface-muted: #eef5f7;
  --ink: #17242b;
  --muted: #5c6c73;
  --line: #dce6ea;
  --section-line: #c7d5dc;
  --blue: #0f4f6e;
  --blue-deep: #0b2f45;
  --teal: #147f7a;
  --gold: #b98221;
  --red: #b94d3e;
  --shadow: 0 16px 36px rgba(15, 47, 69, 0.12);
  --radius: 8px;
  --max: 1160px;
  --font-sans: "Aptos", "Segoe UI", "Apple SD Gothic Neo", "Noto Sans KR", "Malgun Gothic", Arial, sans-serif;
  --font-display: Cambria, Constantia, Georgia, "Times New Roman", Times, serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
}

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

a {
  color: var(--blue);
  text-decoration: none;
}

a:hover {
  color: var(--teal);
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 10;
  background: var(--ink);
  color: #fff;
  padding: 0.55rem 0.8rem;
  border-radius: 6px;
}

.skip-link:focus {
  top: 1rem;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(247, 250, 251, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}

.header-inner {
  width: 100%;
  min-height: 74px;
  padding: 0 32px;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--ink);
  min-width: 0;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  flex: 0 0 48px;
}

.brand-mark img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.brand-text {
  display: grid;
  line-height: 1.15;
}

.brand-name {
  font-weight: 700;
  color: var(--ink);
}

.brand-affiliation {
  color: var(--muted);
  font-size: 0.92rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.22rem;
}

.site-nav a {
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 600;
  padding: 0.56rem 0.6rem;
  border-radius: 6px;
}

.site-nav a:hover,
.site-nav a.is-active {
  background: var(--surface-muted);
  color: var(--blue-deep);
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
}

.hero {
  position: relative;
  min-height: clamp(520px, 72vh, 760px);
  display: grid;
  align-items: center;
  overflow: hidden;
  background:
    linear-gradient(rgba(247, 250, 251, 0.58), rgba(247, 250, 251, 0.58)),
    url("../img/hero-bayesian-lab.png") center center / cover no-repeat;
}

.hero-inner,
.section-inner,
.page-hero-inner {
  width: min(100% - 32px, var(--max));
  margin: 0 auto;
}

.hero-content {
  max-width: 680px;
  padding: 3rem 0 4rem;
}

.eyebrow {
  display: inline-flex;
  color: var(--teal);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
  margin-bottom: 0.95rem;
}

.hero h1,
.page-hero h1 {
  margin: 0;
  color: var(--blue-deep);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2.7rem, 6vw, 5.4rem);
  line-height: 1.08;
  letter-spacing: 0;
  text-wrap: balance;
}

.hero-lead,
.page-lead {
  max-width: 720px;
  margin: 1.4rem 0 0;
  color: #31444d;
  font-size: clamp(1.05rem, 2vw, 1.28rem);
  line-height: 1.72;
}

.hero-quote {
  max-width: 640px;
  margin: 1.4rem 0 0;
  padding: 0.2rem 0 0.2rem 1rem;
  border-left: 3px solid rgba(20, 127, 122, 0.62);
  color: #31444d;
}

.hero-quote p {
  margin: 0;
  color: var(--blue-deep);
  font-family: var(--font-sans);
  font-size: clamp(1.18rem, 2vw, 1.55rem);
  font-weight: 700;
  line-height: 1.35;
}

.hero-quote footer {
  margin-top: 0.35rem;
  color: var(--muted);
  font-size: clamp(1rem, 1.8vw, 1.18rem);
  line-height: 1.45;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin-top: 1.8rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0.72rem 1rem;
  border: 1px solid var(--blue);
  border-radius: 8px;
  background: var(--blue);
  color: #fff;
  font-weight: 650;
}

.button:hover {
  background: var(--blue-deep);
  border-color: var(--blue-deep);
  color: #fff;
}

.button.secondary {
  background: rgba(255, 255, 255, 0.82);
  color: var(--blue-deep);
}

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

.section {
  padding: clamp(3rem, 7vw, 5.5rem) 0;
}

.hero + .section,
.section + .section,
.page-section + .page-section {
  position: relative;
}

.hero + .section::before,
.section + .section::before,
.page-section + .page-section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  width: min(100% - 32px, var(--max));
  height: 1px;
  background: var(--section-line);
  transform: translateX(-50%);
}

.research-areas-section {
  padding-bottom: 1.8rem;
}

.action-section {
  padding-top: 1.6rem;
}

.home-contact {
  margin-top: 2rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--section-line);
}

.home-contact-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.9rem 1.2rem;
}

.home-contact-grid p {
  display: grid;
  gap: 0.15rem;
  margin: 0;
  color: var(--muted);
}

.home-contact-grid strong {
  color: var(--blue-deep);
  font-weight: 700;
}

.section.alt {
  background: var(--surface);
}

.section-header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 2rem;
  margin-bottom: 1.6rem;
}

.section-kicker {
  margin: 0 0 0.2rem;
  color: var(--gold);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

.section h2,
.page-section h2 {
  margin: 0;
  color: var(--blue-deep);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.8rem, 4vw, 2.7rem);
  line-height: 1.1;
  letter-spacing: 0;
}

.section-summary {
  max-width: 660px;
  margin: 0.7rem 0 0;
  color: var(--muted);
}

.text-link {
  display: inline-flex;
  align-items: center;
  color: var(--blue);
  font-weight: 650;
  white-space: nowrap;
}

.grid {
  display: grid;
  gap: 1rem;
}

.grid.three {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

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

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.35rem;
  box-shadow: 0 8px 22px rgba(15, 47, 69, 0.06);
}

.card h3 {
  margin: 0 0 0.45rem;
  color: var(--blue-deep);
  font-size: 1.08rem;
  line-height: 1.25;
}

.card p {
  margin: 0;
  color: var(--muted);
}

.metric {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  margin-bottom: 1rem;
  border-radius: 8px;
  background: var(--surface-muted);
  color: var(--blue);
  font-weight: 900;
}

.publication-list,
.software-list,
.project-list {
  display: grid;
  gap: 0.8rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.publication-group-header {
  margin-top: 3rem;
}

.section-inner > .publication-group-header:first-child {
  margin-top: 0;
}

.publication-year {
  margin: 1.3rem 0 0.7rem;
  color: var(--gold);
  font-size: 0.84rem;
  font-weight: 900;
}

.software-list {
  gap: 0.55rem;
}

.software-line {
  color: var(--muted);
  font-size: 1rem;
}

.software-line a,
.software-line strong {
  color: var(--blue-deep);
  font-weight: 650;
}

.publication-item,
.software-item,
.project-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1rem 1.1rem;
}

.publication-meta,
.item-meta {
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 700;
}

.software-item h3,
.project-item h3 {
  margin: 0.15rem 0 0;
  color: var(--blue-deep);
  font-size: 1.02rem;
}

.photo-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.2rem;
}

.photo-item {
  margin: 0;
}

.gallery-photo-button {
  display: block;
  width: 100%;
  padding: 0;
  border: 0;
  border-radius: var(--radius);
  background: transparent;
  cursor: zoom-in;
}

.gallery-photo-button:focus-visible {
  outline: 3px solid rgba(20, 127, 122, 0.35);
  outline-offset: 3px;
}

.photo-item img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: var(--radius);
}

.photo-item figcaption {
  display: grid;
  gap: 0.15rem;
  margin-top: 0.55rem;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.45;
}

.photo-item figcaption strong {
  color: var(--blue-deep);
}

.photo-item figcaption a {
  color: var(--blue);
  font-weight: 800;
}

.empty-state {
  border: 1px dashed #b8c9d1;
  border-radius: var(--radius);
  padding: 1.3rem;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.64);
}

.page-hero {
  padding: clamp(3rem, 8vw, 6rem) 0 clamp(2.4rem, 6vw, 4rem);
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}

.page-section {
  padding: clamp(2.4rem, 6vw, 4.5rem) 0;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(2rem, 5vw, 4rem);
  align-items: start;
}

.prose {
  color: #334851;
}

.prose p {
  margin-top: 0;
}

.prose ul {
  margin: 0;
  padding-left: 1.2rem;
}

.prose li + li {
  margin-top: 0.5rem;
}

.topic-list {
  display: grid;
  gap: 1rem;
}

.topic {
  border-left: 4px solid var(--teal);
  padding: 0.25rem 0 0.25rem 1rem;
}

.topic h3 {
  margin: 0 0 0.25rem;
  color: var(--blue-deep);
}

.topic p {
  margin: 0;
  color: var(--muted);
}

.people-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.people-grid-pi {
  grid-template-columns: minmax(0, 360px);
  margin-bottom: 3rem;
}

.people-grid + .section-header {
  margin-top: 3rem;
}

.person-card {
  display: grid;
  grid-template-columns: 112px minmax(0, 1fr);
  gap: 1rem;
  align-items: center;
  background: transparent;
  border: 0;
  border-radius: 0;
  overflow: visible;
  box-shadow: none;
}

.person-photo-button {
  width: 112px;
  height: 112px;
  padding: 0;
  border: 0;
  border-radius: var(--radius);
  background: transparent;
  cursor: zoom-in;
}

.person-photo-button:focus-visible {
  outline: 3px solid rgba(20, 127, 122, 0.35);
  outline-offset: 3px;
}

.person-photo-button img {
  width: 112px;
  height: 112px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  object-fit: cover;
  object-position: var(--photo-position, center 24%);
  padding: 0;
  background: transparent;
}

.photo-modal {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
}

.photo-modal.is-open {
  display: flex;
}

.photo-modal-backdrop {
  position: absolute;
  inset: 0;
  border: 0;
  background: rgba(11, 47, 69, 0.72);
  cursor: zoom-out;
}

.photo-modal-dialog {
  position: relative;
  z-index: 1;
  max-width: min(90vw, 720px);
  max-height: 88vh;
}

.photo-modal-dialog img {
  max-width: 100%;
  max-height: 82vh;
  border-radius: var(--radius);
  background: #fff;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.28);
}

.photo-modal-close {
  position: absolute;
  right: 0;
  bottom: calc(100% + 0.65rem);
  min-height: 36px;
  padding: 0.4rem 0.7rem;
  border: 1px solid rgba(255, 255, 255, 0.5);
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.92);
  color: var(--blue-deep);
  font-weight: 800;
  cursor: pointer;
}

.person-body {
  min-width: 0;
  padding: 0;
}

.person-body h3 {
  margin: 0;
  color: var(--blue-deep);
}

.person-position {
  margin: 0.15rem 0 0.65rem;
  color: var(--gold);
  font-weight: 650;
  font-size: 0.9rem;
}

.person-body p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.person-current {
  margin-top: 0.25rem;
  color: #334851;
  font-weight: 700;
}

.person-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 0.9rem;
  font-weight: 650;
  font-size: 0.9rem;
}

.publication-item {
  display: grid;
  gap: 0.35rem;
}

.publication-title {
  margin: 0;
  color: var(--blue-deep);
  font-size: 1.04rem;
  font-weight: 650;
}

.publication-authors,
.publication-venue {
  margin: 0;
  color: var(--muted);
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 0.8rem;
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0.24rem 0.55rem;
  border-radius: 6px;
  background: var(--surface-muted);
  color: var(--blue-deep);
  font-size: 0.82rem;
  font-weight: 800;
}

.contact-panel {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.contact-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.25rem;
}

.contact-item h3 {
  margin: 0 0 0.4rem;
  color: var(--blue-deep);
}

.contact-item p {
  margin: 0;
  color: var(--muted);
}

.site-footer {
  border-top: 1px solid var(--line);
  background: var(--blue-deep);
  color: #dce8ee;
}

.footer-inner {
  width: min(100% - 32px, var(--max));
  margin: 0 auto;
  padding: 2rem 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.footer-inner p {
  margin: 0.25rem 0 0;
  color: #adc3cd;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-weight: 800;
}

.footer-links a {
  color: #e6f2f5;
}

@media (max-width: 920px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 74px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 0.6rem;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--surface);
    box-shadow: var(--shadow);
  }

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

  .site-nav a {
    padding: 0.75rem 0.9rem;
  }

  .hero {
    background:
      linear-gradient(rgba(247, 250, 251, 0.72), rgba(247, 250, 251, 0.72)),
      url("../img/hero-bayesian-lab.png") center center / cover no-repeat;
  }

  .grid.three,
  .grid.two,
  .split,
  .people-grid,
  .photo-grid,
  .home-contact,
  .home-contact-grid,
  .contact-panel {
    grid-template-columns: 1fr;
  }

  .section-header {
    display: block;
  }

  .section-header .text-link {
    margin-top: 0.9rem;
  }
}

@media (max-width: 560px) {
  .header-inner,
  .hero-inner,
  .section-inner,
  .page-hero-inner,
  .footer-inner {
    width: min(100% - 24px, var(--max));
  }

  .header-inner {
    width: 100%;
    padding: 0 12px;
  }

  .brand-name {
    font-size: 0.95rem;
  }

  .brand-affiliation {
    font-size: 0.82rem;
  }

  .hero {
    min-height: 640px;
    align-items: start;
  }

  .hero-content {
    padding-top: 4.5rem;
  }

  .hero h1,
  .page-hero h1 {
    font-size: 2.55rem;
  }

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

  .button {
    width: 100%;
  }

  .card,
  .publication-item,
  .software-item,
  .project-item,
  .contact-item {
    padding: 1rem;
  }

  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }
}