/* ── RESET & ROOT ──────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --navy:      #191A1D;   /* near-black — headings, dark sections */
  --navy-mid:  #232427;
  --blue:      #2B5A96;   /* single muted accent */
  --blue-lt:   #6C8FBE;
  --gold:      #2B5A96;   /* accent (legacy name, kept for low diff) */
  --gold-lt:   #EEF2F7;   /* pale accent tint */
  --gold-dk:   #2B5A96;   /* accent for labels/links on light bg */
  --bg:        #FFFFFF;
  --bg-alt:    #F6F7F8;
  --white:     #FFFFFF;
  --text:      #1A1A1A;
  --text-mid:  #5A5D63;
  --text-lt:   #8A8D93;
  --border:    #E3E5E8;

  --font-serif: var(--font-sans);
  --font-sans:  'Inter', -apple-system, BlinkMacSystemFont, sans-serif;

  --radius-sm: 4px;
  --radius:    6px;
  --radius-lg: 8px;

  --shadow-sm: none;
  --shadow:    0 1px 3px rgba(0,0,0,.05);
  --shadow-lg: 0 4px 16px rgba(0,0,0,.08);

  --transition: 0.2s ease;
}

html { font-size: 16px; }

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ── PAGE CONTENT ───────────────────────────────────────────── */
#main-content {
  flex: 1;
  animation: pageFadeIn 0.35s ease forwards;
}

@keyframes pageFadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}


a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* ── UTILITY ───────────────────────────────────────────────── */
.container {
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
}
.container-narrow { max-width: 860px; }

.section { padding: 96px 0; }
.section-alt {
  background-color: var(--bg-alt);
}
.section-dark {
  background: var(--navy);
  color: var(--white);
}

.section-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--gold-dk);
  margin-bottom: 12px;
}
.section-label.light { color: var(--gold-lt); }

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 2.75rem);
  line-height: 1.15;
  color: var(--navy);
  margin-bottom: 16px;
}
.section-title.centered { text-align: center; }
.section-title.light { color: var(--white); }

.section-desc {
  font-size: 1.05rem;
  color: var(--text-mid);
  max-width: 600px;
  margin-bottom: 56px;
}
.section-desc.centered { margin-left: auto; margin-right: auto; text-align: center; }

/* ── SECTION HEADERS ─────────────────────────────────────── */
.section-header {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 24px;
  margin-bottom: 48px;
}
.section-header-text { display: flex; flex-direction: column; }
.section-kicker {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--gold-dk);
  margin-bottom: 4px;
}
.section-dark .section-kicker { color: var(--gold-lt); }
.section-header .section-title { margin-bottom: 0; }
.section-header-line {
  height: 1px;
  background: linear-gradient(90deg, var(--border) 0%, transparent 100%);
  min-width: 40px;
  flex: 1;
}
.section-dark .section-header-line {
  background: linear-gradient(90deg, rgba(255,255,255,.18) 0%, transparent 100%);
}

/* Fade-in on scroll */
.fade-in {
  opacity: 0;
  transform: translateY(32px) scale(0.98);
  transition: opacity 0.7s cubic-bezier(0.4,0,0.2,1),
              transform 0.7s cubic-bezier(0.4,0,0.2,1);
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0) scale(1);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius-sm);
  font-size: .925rem;
  font-weight: 600;
  letter-spacing: .02em;
  transition: var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
}
.btn-primary {
  background: #1E3A5F;
  border-color: #A8C8E8;
  color: #E8F4FF;
}
.btn-primary:hover { background: #A8C8E8; color: #0A1628; }

.btn-outline {
  border-color: currentColor;
  color: var(--navy);
}
.btn-outline:hover { background: var(--navy); color: var(--white); }

.section-dark .btn-outline {
  color: var(--white);
  border-color: rgba(255,255,255,.4);
}
.section-dark .btn-outline:hover { background: rgba(255,255,255,.15); }

/* Tags */
.tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  font-size: .8rem;
  font-weight: 500;
  color: var(--text-mid);
}

/* ── NAVBAR ────────────────────────────────────────────────── */
#navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  padding: 18px 0;
  background: var(--white);
  border-bottom: 1px solid var(--border);
  transition: padding var(--transition);
  isolation: isolate;
}
#navbar.scrolled {
  padding: 12px 0;
}

.nav-inner {
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 14px;
}
.nav-brand-divider {
  width: 1px;
  height: 22px;
  background: var(--border);
}
.nav-logo {
  display: flex;
  align-items: center;
}
.nav-logo img {
  height: 26px;
  width: auto;
  display: block;
}

.nav-links {
  display: grid;
  grid-template-columns: 180px 180px 130px 130px;
  list-style: none;
}
.nav-links > li { text-align: center; }
.nav-links a {
  font-size: .95rem;
  font-weight: 500;
  color: var(--text-mid);
  transition: color var(--transition);
  letter-spacing: .01em;
}
.nav-links a:hover { color: var(--text); }
.nav-links a.nav-active { color: var(--blue); }

/* Dropdown */
.has-dropdown { position: relative; }
.nav-dropdown {
  opacity: 0;
  pointer-events: none;
  visibility: hidden;
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%) translateY(-4px);
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 6px 0;
  min-width: 200px;
  list-style: none;
  z-index: 1100;
  box-shadow: var(--shadow-lg);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
}
.has-dropdown:hover .nav-dropdown,
.has-dropdown.open .nav-dropdown {
  opacity: 1;
  pointer-events: auto;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}
.nav-dropdown li a {
  display: block;
  padding: 9px 20px;
  font-size: .825rem;
  font-weight: 500;
  color: var(--text-mid);
  white-space: nowrap;
  transition: color var(--transition), background var(--transition);
}
.nav-dropdown li a:hover { color: var(--blue); background: var(--bg-alt); }
.nav-dropdown li a.nav-active { color: var(--blue); }
.nav-dropdown-email {
  display: block;
  padding: 9px 20px;
  font-size: .78rem;
  font-weight: 400;
  color: var(--text-lt);
  white-space: nowrap;
  letter-spacing: .01em;
  transition: color var(--transition);
}
.nav-dropdown-email:hover { color: var(--blue); }

/* ── On desktop, individual dropdowns are replaced by the mega menu ── */
@media (min-width: 768px) {
  .nav-dropdown { display: none !important; }
}

/* ── MEGA MENU ───────────────────────────────────────────────────── */
#mega-menu {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: var(--white);
  border-bottom: 1px solid var(--border);
  padding: 28px 0;
  opacity: 0;
  pointer-events: none;
  transform: translateY(-4px);
  transition: opacity 200ms ease, transform 200ms ease;
  z-index: 999;
  box-shadow: var(--shadow-lg);
}
#mega-menu.open {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}
@media (max-width: 767px) {
  #mega-menu { display: none; }
}
.mega-inner {
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 180px 180px 130px 130px;
  justify-content: end;
}
.mega-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 0 4px;
}
.mega-col + .mega-col {
  border-left: 1px solid var(--border);
}
.mega-link {
  font-size: .95rem;
  color: var(--text-mid);
  padding: 9px 20px;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  transition: background 150ms ease, color 150ms ease;
  display: block;
  text-align: center;
}
.mega-link:hover {
  background: var(--bg-alt);
  color: var(--text);
}
.mega-link.nav-active { color: var(--blue); font-weight: 600; }

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: var(--transition);
}

/* ── HERO ───────────────────────────────────────────────────── */
#hero {
  position: relative;
  min-height: 66vh;
  padding: 140px 0 80px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--navy);
  overflow: hidden;
}

#hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
}

/* bottom fade into the section below */
#hero::before {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 90px;
  background: linear-gradient(to bottom, transparent 0%, var(--white) 100%);
  z-index: 1;
  pointer-events: none;
}

/* subtle accent wash */
#hero::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg,
    rgba(43,90,150,.22) 0%,
    rgba(43,90,150,0) 55%);
  z-index: 1;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 0 24px;
  max-width: 720px;
}

.hero-logo {
  height: 56px;
  width: auto;
  margin: 0 auto 40px;
  filter: invert(1);
}

.hero-sub {
  font-size: .8rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: rgba(255,255,255,.6);
  margin-bottom: 20px;
}

.hero-welcome {
  font-size: clamp(1.6rem, 3.4vw, 2.1rem);
  font-weight: 600;
  color: var(--white);
  line-height: 1.3;
  margin-bottom: 16px;
}

.hero-statement {
  font-size: 1.05rem;
  color: rgba(255,255,255,.72);
  line-height: 1.7;
  margin-bottom: 28px;
}
.hero-statement a {
  color: var(--blue-lt);
  font-weight: 600;
  transition: color var(--transition);
}
.hero-statement a:hover {
  color: var(--white);
  text-decoration: underline;
}

.hero-tags {
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-tag {
  padding: 5px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  color: var(--text-mid);
  font-size: .8rem;
  font-weight: 500;
}

.scroll-hint {
  position: absolute;
  bottom: 108px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2;
  color: rgba(255,255,255,.6);
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}
.scroll-hint svg { width: 22px; height: 22px; }

/* ── ABOUT ──────────────────────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 64px;
  align-items: center;
  margin-bottom: 56px;
}

.about-pi {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.pi-avatar {
  width: 168px;
  height: 168px;
  border-radius: var(--radius-lg);
  background: var(--bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  overflow: hidden;
  flex-shrink: 0;
}
.pi-photo {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  display: block;
}
.pi-avatar-initials {
  display: none;
  width: 100%;
  height: 100%;
  background: var(--bg-alt);
}

.pi-name {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  color: var(--navy);
  margin-bottom: 4px;
}
.pi-name-kr {
  font-family: var(--font-sans);
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--text-lt);
  margin-left: 8px;
}
.pi-title {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--gold-dk);
  margin-bottom: 12px;
}
.pi-dept {
  font-size: .875rem;
  color: var(--text-mid);
  line-height: 1.5;
  margin-bottom: 20px;
}
.pi-links {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}
.pi-link {
  font-size: .875rem;
  font-weight: 600;
  color: var(--blue);
  transition: color var(--transition);
}
.pi-link:hover { color: var(--navy); }

.pi-social-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px;
  margin-top: 14px;
}
.pi-social-links-top {
  justify-content: flex-start;
  margin-top: 18px;
  margin-bottom: 0;
}
.pi-social-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: .7rem;
  font-weight: 600;
  color: var(--blue);
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.pi-social-link:hover {
  background: var(--blue);
  color: #fff;
  border-color: var(--blue);
}

/* ── PI PROFILE (About page) ────────────────────────────────── */
.pi-profile {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 48px;
  align-items: start;
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 40px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  margin-bottom: 0;
}
.pi-intro {
  display: flex;
  flex-direction: column;
  gap: 20px;
  justify-content: flex-start;
}
.pi-intro .pi-section {
  padding: 0;
  border-top: none;
  grid-template-columns: 110px 1fr;
  gap: 20px;
}
.pi-section-bio {
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.pi-intro-bio {
  font-size: .9rem;
  color: var(--text-mid);
  line-height: 1.8;
}
.pi-intro-interests {
  border-left: 3px solid var(--blue);
  padding-left: 16px;
}
.pi-intro-interests-label {
  font-size: .75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--blue);
  margin-bottom: 6px;
}
.pi-intro-interests-text {
  font-size: .875rem;
  color: var(--text-lt);
  line-height: 1.7;
  font-style: italic;
}

/* ── PI SECTIONS (reference-style) ─────────────────────── */
.pi-sections {
  background: var(--white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  margin-top: 16px;
  overflow: hidden;
}
.pi-section {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 48px;
  padding: 40px 40px;
  border-top: 1px solid var(--border);
}
.pi-section:first-child {
  border-top: none;
}
.pi-section-label {
  font-size: 13.5px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--blue);
  line-height: 1.5;
  padding-top: 3px;
}
.pi-section-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.pi-section-list > li {
  font-size: .9rem;
  color: var(--text-mid);
  line-height: 1.6;
  padding-left: 14px;
  position: relative;
}
.pi-section-list > li::before {
  content: '·';
  position: absolute;
  left: 0;
  color: var(--blue);
  font-weight: 700;
}
.pi-section-list a,
.pi-section-bio a {
  color: var(--blue);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--blue) 40%, transparent);
  text-underline-offset: 2px;
  transition: color var(--transition), text-decoration-color var(--transition);
}
.pi-section-list a:hover,
.pi-section-bio a:hover {
  color: var(--blue-dark, var(--blue));
  text-decoration-color: var(--blue);
}

.pi-profile-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.pi-bio {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.pi-bio-block p {
  font-size: .9rem;
  color: var(--text-mid);
  line-height: 1.65;
  margin: 0;
}

.pi-bio-heading {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--gold-dk);
  margin-bottom: 8px;
}

.pi-bio-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.pi-bio-list li {
  font-size: .9rem;
  color: var(--text-mid);
  line-height: 1.55;
  padding-left: 16px;
  position: relative;
}

.pi-bio-list li::before {
  content: '–';
  position: absolute;
  left: 0;
  color: var(--gold);
  font-weight: 600;
}

.pi-bio-note {
  font-size: .82rem;
  color: var(--text-lt);
  font-style: italic;
}

/* ── COURSES ───────────────────────────────────────────────────── */
.course-uni {
  margin-bottom: 52px;
}

.course-uni-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--navy);
}

.course-uni-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--navy);
  color: var(--white);
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .05em;
  flex-shrink: 0;
}

.course-uni-name {
  font-family: var(--font-serif);
  font-size: clamp(1.2rem, 2vw, 1.5rem);
  color: var(--navy);
}

.course-program {
  margin-bottom: 32px;
}

.course-program-title {
  font-size: .78rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 14px;
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}

.course-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.course-level {
  font-size: .68rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--text-lt);
}

.course-name {
  font-size: .95rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.4;
}

.course-code {
  font-size: .78rem;
  color: var(--text-lt);
  font-family: monospace;
}

.course-period {
  font-size: .80rem;
  color: var(--text-mid);
}

.course-role {
  display: inline-block;
  margin-top: 4px;
  font-size: .70rem;
  font-weight: 600;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--blue);
  background: var(--gold-lt);
  border-radius: 4px;
  padding: 2px 8px;
  width: fit-content;
}

.about-vision-img {
  display: block;
  margin: 0 auto;
  width: 100%;
  max-width: 860px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: 0 2px 14px rgba(0,0,0,.06);
}

/* ── LEGACY OF FDCL (About page) ─────────────────────────────── */
.legacy-section {
  margin-top: 0;
  padding-top: 0;
  border-top: none;
}

.legacy-desc {
  color: var(--text-mid);
  font-size: 1rem;
  max-width: 780px;
  margin: 0 auto 32px;
  text-align: center;
  line-height: 1.75;
}
.legacy-desc-kr {
  margin-top: -20px;
  font-size: .95rem;
  color: var(--text-lt);
}

.legacy-img {
  margin-bottom: 40px;
}

.legacy-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 8px;
}

.legacy-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 24px 28px;
}

.legacy-card-current {
  border-color: var(--blue);
  background: var(--gold-lt);
}

.legacy-gen {
  display: inline-block;
  font-size: .68rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 10px;
}

.legacy-name {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  color: var(--navy);
  margin-bottom: 4px;
}

.legacy-period {
  font-size: .82rem;
  color: var(--text-lt);
  margin-bottom: 14px;
}

.legacy-edu {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.legacy-edu li {
  font-size: .82rem;
  color: var(--text-mid);
  padding-left: 14px;
  position: relative;
}

.legacy-edu li::before {
  content: "·";
  position: absolute;
  left: 0;
  color: var(--blue);
  font-weight: 700;
}

@media (max-width: 700px) {
  .legacy-grid { grid-template-columns: 1fr; }
}

.join-banner {
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-mid) 100%);
  border-radius: var(--radius-lg);
  padding: 40px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  color: var(--white);
}
.join-text h3 {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  margin-bottom: 8px;
}
.join-text p {
  color: rgba(255,255,255,.7);
  font-size: .95rem;
}

/* ── RESEARCH CONTENT (compiled from markdown) ──────────────────── */
.research-content h2 {
  font-size: clamp(1.4rem, 2.6vw, 1.8rem);
  font-weight: 700;
  color: var(--text);
  margin: 48px 0 20px;
}
.research-content h2:first-child { margin-top: 0; }
.research-content h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  margin: 32px 0 14px;
}
.research-content p {
  font-size: .95rem;
  color: var(--text-mid);
  line-height: 1.8;
  margin-bottom: 20px;
}
.research-content p > em:first-child:last-child {
  display: block;
  font-size: 1.05rem;
  font-style: normal;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 24px;
}
.research-content img {
  display: block;
  width: 100%;
  max-width: 100%;
  margin: 0 auto 28px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.research-content ul {
  list-style: none;
  padding: 0;
  margin: 0 0 32px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.research-content li {
  font-size: .95rem;
  color: var(--text-mid);
  padding-left: 20px;
  position: relative;
  line-height: 1.5;
}
.research-content li::before {
  content: '–';
  position: absolute;
  left: 0;
  color: var(--blue);
}
.research-content li em {
  color: var(--text);
  font-style: normal;
  font-weight: 500;
}

/* ── TEASER SECTIONS ─────────────────────────────────────────── */
.teaser-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.teaser-title {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--navy);
  line-height: 1.2;
  margin-top: 4px;
}

/* ── PUBLICATIONS ─────────────────────────────────────────────── */
.pub-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 48px;
  justify-content: center;
  flex-wrap: wrap;
}
.pub-tab {
  padding: 8px 22px;
  border-radius: 999px;
  border: 2px solid var(--border);
  background: var(--white);
  font-size: .875rem;
  font-weight: 600;
  color: var(--text-mid);
  cursor: pointer;
  transition: var(--transition);
}
.pub-tab:hover { border-color: var(--blue); color: var(--blue); }
.pub-tab.active {
  background: var(--navy);
  border-color: var(--navy);
  color: var(--white);
}

.pub-year-group { margin-bottom: 40px; }
.pub-year-group.hidden { display: none; }

.pub-year-label {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--navy);
  padding-bottom: 12px;
  border-bottom: 2px solid var(--gold);
  margin-bottom: 20px;
}

.pub-item {
  display: flex;
  gap: 16px;
  padding: 20px 24px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
}
.pub-item.hidden { display: none; }

.pub-badge {
  flex-shrink: 0;
  width: 124px;           /* fits the longest label ("Dissertation") so all badges align */
  text-align: center;
  padding: 4px 6px;
  border-radius: 999px;
  font-size: .78rem;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
  height: fit-content;
  margin-top: 3px;
}
.pub-badge.journal  { background: #E8F3FF; color: #1A6EB5; }
.pub-badge.conference { background: #EFF8F0; color: #1D7A35; }
.pub-badge.preprint { background: #FFF4E5; color: #9B5200; }
.pub-badge.korean   { background: linear-gradient(180deg, #FCE4E7 0%, #FCE4E7 30%, #E1EAF8 70%, #E1EAF8 100%); color: #3B3F8C; }
.pub-badge.report   { background: #EEF0F3; color: #4A5260; }
.pub-badge.thesis   { background: #FCEEF0; color: #A33347; }

.pub-title {
  display: block;
  font-size: .95rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 4px;
  line-height: 1.45;
}
.pub-authors {
  font-size: .85rem;
  color: var(--text-mid);
  margin-bottom: 2px;
}
.pub-venue {
  font-size: .825rem;
  color: var(--text-lt);
  font-style: italic;
}
a.pub-title {
  color: var(--text);
  display: block;
  font-size: .95rem;
  font-weight: 600;
  line-height: 1.45;
  margin-bottom: 4px;
  transition: color var(--transition);
}
a.pub-title:hover { color: var(--blue); text-decoration: underline; }
.pub-link-icon {
  width: 12px;
  height: 12px;
  margin-left: 6px;
  vertical-align: -1px;
  color: var(--text-lt);
  transition: color var(--transition);
}
a.pub-title:hover .pub-link-icon { color: var(--blue); }

.pub-doi {
  display: inline-block;
  margin-top: 4px;
  font-size: .78rem;
  color: var(--text-lt);
  text-decoration: underline;
  text-decoration-style: dotted;
  text-underline-offset: 2px;
  transition: color var(--transition);
}
.pub-doi:hover { color: var(--blue); }

.pub-more { text-align: center; margin-top: 48px; }

.gallery-card { cursor: pointer; }

/* ── MEMBERS ──────────────────────────────────────────────────── */
.members-group { margin-bottom: 56px; }
.members-group-title {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  color: var(--navy);
  margin-bottom: 4px;
}
.members-group-note {
  font-family: var(--font-sans);
  font-size: .85rem;
  font-weight: 400;
  color: var(--text-lt);
}

.members-subgroup { margin-bottom: 32px; margin-top: 24px; }
.members-subgroup-title {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--text-lt);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.members-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.members-grid-cols3 {
  grid-template-columns: repeat(3, 1fr);
}
@media (max-width: 980px) {
  .members-grid-cols3 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 620px) {
  .members-grid-cols3 { grid-template-columns: 1fr; }
}

.member-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 24px 28px;
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  gap: 24px;
  border: 1px solid var(--border);
}
.member-card-highlight {
  border-color: var(--gold);
  background: #FFFCF5;
}

.members-grid-cols3 .member-card {
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 14px;
}
.members-grid-cols3 .member-info { text-align: center; }
.members-grid-cols3 .member-interests { justify-content: center; }

.member-photo-wrap {
  flex-shrink: 0;
  position: relative;
  width: 174px;
  height: 174px;
}
.member-photo {
  width: 174px;
  height: 174px;
  border-radius: var(--radius);
  object-fit: contain;
}

.member-avatar {
  width: 174px;
  height: 174px;
  border-radius: var(--radius);
  background: var(--bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-lt);
  letter-spacing: .04em;
  box-shadow: 0 0 0 3px var(--bg);
  border: 1px solid var(--border);
}
.avatar-phd, .avatar-msc, .avatar-bsc { background: var(--bg-alt); }
.member-avatar-icon {
  width: 40%;
  height: 40%;
}

.member-info {
  text-align: left;
  flex: 1;
  min-width: 0;
}
.member-name {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 3px;
}
.member-name-kr {
  font-size: 1rem;
  font-weight: 400;
  color: var(--text);
  margin-left: 8px;
}
.member-badge {
  display: inline-block;
  font-size: .65rem;
  font-weight: 700;
  letter-spacing: .07em;
  text-transform: uppercase;
  color: #7A5800;
  background: #FFF3CD;
  border: 1px solid #F0D060;
  border-radius: 99px;
  padding: 1px 8px;
  margin-left: 8px;
  vertical-align: middle;
}
.member-role {
  font-size: .82rem;
  font-weight: 600;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 5px;
}
.member-note {
  font-size: .85rem;
  color: var(--text-lt);
  line-height: 1.4;
}
.member-email {
  display: inline-block;
  font-size: .82rem;
  color: var(--blue);
  text-decoration: none;
  margin-top: 5px;
  word-break: break-all;
}
.member-email:hover { text-decoration: underline; }
.member-research {
  font-size: .82rem;
  color: var(--text-lt);
  line-height: 1.4;
  margin-top: 6px;
}
.member-research-label {
  font-weight: 600;
  color: var(--text-mid);
}
.member-link-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 20px;
  height: 20px;
  margin-left: 8px;
  vertical-align: middle;
  color: var(--text-lt);
  border-radius: 50%;
  transition: color var(--transition), background var(--transition);
}
.member-link-icon svg {
  width: 14px;
  height: 14px;
}
.member-link-icon:hover {
  color: var(--white);
  background: var(--blue);
}
.member-interests {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  justify-content: flex-start;
  margin-top: 10px;
}
.member-interest-tag {
  font-size: .72rem;
  padding: 3px 10px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 99px;
  color: var(--text-mid);
}

/* ── NEWS ─────────────────────────────────────────────────────── */
.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.news-card {
  background: var(--white);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
}
.gallery-card {
  transition: box-shadow var(--transition), border-color var(--transition);
}
.gallery-card:hover {
  box-shadow: var(--shadow-lg);
  border-color: var(--gold);
}

.news-card-img {
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--bg-alt);
}
.news-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.5s ease;
}
.gallery-card:hover .news-card-img img { transform: scale(1.04); }

.news-card-placeholder {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-mid) 100%);
}
.news-card-placeholder span:first-child {
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--gold);
}
.news-card-placeholder span:last-child {
  font-size: .85rem;
  color: rgba(255,255,255,.45);
}

.news-card-body { padding: 20px 22px 24px; }

.news-card-date {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--gold-dk);
  margin-bottom: 8px;
}
.news-card-title {
  font-weight: 600;
  font-size: .95rem;
  color: var(--text);
  margin-bottom: 8px;
  line-height: 1.45;
}
.news-card-text {
  font-size: .85rem;
  color: var(--text-mid);
  line-height: 1.6;
  margin: 0;
}

/* ── CONTACT ──────────────────────────────────────────────────── */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.contact-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 28px;
  text-align: center;
  min-height: 220px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.contact-icon {
  width: 52px;
  height: 52px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
}
.contact-icon svg { width: 22px; height: 22px; stroke: var(--text); }

.contact-card h3 {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--gold-dk);
  margin-bottom: 12px;
}
.contact-card p {
  font-size: .9rem;
  color: var(--text-mid);
  line-height: 1.6;
}
.contact-link {
  color: var(--blue);
  font-weight: 600;
  transition: color var(--transition);
}
.contact-link:hover { color: var(--text); }

.contact-address-label {
  display: inline-block;
  font-size: .65rem;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--text-mid);
  background: var(--bg-alt);
  border-radius: 4px;
  padding: 1px 5px;
  margin-right: 4px;
}

.contact-bottom {
  display: flex;
  gap: 24px;
  align-items: stretch;
  margin-bottom: 0;
}
.contact-map {
  flex: 1.4;
  min-height: 420px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
}
.contact-map iframe { display: block; height: 100%; min-height: 420px; }
.contact-bottom .join-cta { flex: 1; }
@media (max-width: 700px) {
  .contact-bottom { flex-direction: column; }
  .contact-map { min-height: 240px; }
}

.contact-card.join-cta h3 { font-size: 1.15rem; margin-bottom: 16px; }
.join-cta p + p { margin-top: 6px; }
.join-cta a {
  color: var(--blue);
  text-decoration: underline;
}

/* ── BOARD LIST (News 게시판) ────────────────────────────────── */
.board-list { width: 100%; }

.board-list-header {
  display: grid;
  grid-template-columns: 56px 1fr 96px;
  padding: 10px 16px;
  border-top: 2px solid var(--navy);
  border-bottom: 2px solid var(--border);
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--text-mid);
}

.board-row {
  display: grid;
  grid-template-columns: 56px 1fr 96px;
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: background var(--transition);
  align-items: center;
}
.board-row:hover { background: var(--bg-alt); }

.board-col-num {
  font-size: .82rem;
  color: var(--text-lt);
  text-align: center;
}
.board-col-title {
  font-size: .925rem;
  font-weight: 600;
  color: var(--text);
  transition: color var(--transition);
}
.board-row:hover .board-col-title { color: var(--blue); }
.board-col-date {
  font-size: .8rem;
  color: var(--text-lt);
  text-align: right;
}

/* ── GALLERY MODAL ──────────────────────────────────────────── */
.gallery-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 500;
  align-items: center;
  justify-content: center;
  padding: 24px;
}
.gallery-modal.open { display: flex; }

.gallery-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.72);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}

.gallery-modal-dialog {
  position: relative;
  z-index: 1;
  background: var(--white);
  border-radius: var(--radius-lg);
  max-width: 720px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 32px 80px rgba(0,0,0,.45);
  animation: modalIn 0.25s cubic-bezier(0.4,0,0.2,1);
}
@keyframes modalIn {
  from { opacity: 0; transform: scale(0.96) translateY(12px); }
  to   { opacity: 1; transform: scale(1) translateY(0); }
}

.gallery-modal-close {
  position: absolute;
  top: 14px;
  right: 14px;
  z-index: 2;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(0,0,0,.5);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  transition: background var(--transition);
}
.gallery-modal-close:hover { background: var(--navy); }
.gallery-modal-close svg { width: 18px; height: 18px; }

.gallery-modal-img-wrap {
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  background: var(--navy);
}
.gallery-modal-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.gallery-modal-info { padding: 28px 32px 36px; }

.gallery-modal-date {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--gold-dk);
  margin-bottom: 8px;
}
.gallery-modal-title {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  color: var(--navy);
  margin-bottom: 16px;
  line-height: 1.2;
}
.gallery-modal-text {
  font-size: .925rem;
  color: var(--text-mid);
  line-height: 1.7;
  white-space: pre-wrap;
}

/* ── GO TO TOP ───────────────────────────────────────────────── */
.go-top {
  position: fixed;
  bottom: 36px;
  right: 36px;
  z-index: 200;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--navy);
  border: 2px solid var(--gold);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.3s ease, transform 0.3s ease,
              background 0.3s ease, color 0.3s ease;
}
.go-top.visible { opacity: 1; pointer-events: auto; transform: translateY(0); }
.go-top:hover { background: var(--gold); color: var(--navy); }
.go-top svg { width: 18px; height: 18px; }

/* ── FOOTER ───────────────────────────────────────────────────── */
.footer {
  background: var(--bg-alt);
  color: var(--text-mid);
  padding: 40px 0;
  border-top: 1px solid var(--border);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 14px;
}
.footer-logo img {
  height: 20px;
  width: auto;
  display: block;
}
.footer-snu-logo {
  height: 36px;
  width: auto;
  display: block;
}

.footer-copy {
  padding-top: 20px;
  border-top: 1px solid var(--border);
}
.footer-copy p {
  font-size: .8rem;
  color: var(--text-lt);
}

/* ── RESPONSIVE ───────────────────────────────────────────────── */
@media (max-width: 960px) {
  .about-grid { grid-template-columns: 1fr; gap: 36px; }
  .about-pi { flex-direction: row; text-align: left; }

  .pi-profile { grid-template-columns: 1fr; gap: 32px; }
  .pi-profile-card { flex-direction: row; text-align: left; gap: 24px; align-items: flex-start; }
  .pi-section { grid-template-columns: 140px 1fr; gap: 28px; padding: 32px 32px; }

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

  .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .section { padding: 64px 0; }

  .hamburger { display: flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--white);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 24px;
    gap: 20px;
  }
  .nav-links.open { display: flex; }

  .teaser-header { flex-direction: column; align-items: flex-start; }

  .about-pi { flex-direction: column; text-align: center; }

  .pi-profile { padding: 24px; }
  .pi-profile-card { flex-direction: column; text-align: center; align-items: center; }
  .pi-section { grid-template-columns: 1fr; gap: 16px; padding: 24px; }
  .pi-section-label { padding-top: 0; }

  .news-grid { grid-template-columns: 1fr; }

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

  .section-header { grid-template-columns: 1fr; gap: 12px; }
  .section-header-line { display: none; }
  .go-top { bottom: 20px; right: 20px; }

  .gallery-modal { padding: 16px; }
  .gallery-modal-info { padding: 20px 20px 28px; }
  .gallery-modal-title { font-size: 1.25rem; }
}

@media (max-width: 480px) {
  .contact-grid { grid-template-columns: 1fr; }
}

/* ── PROJECTS PAGE ───────────────────────────────────────────────── */
/* ── PROJECT TABS ─────────────────────────────────── */
.proj-tabs-wrap {
  display: flex;
  gap: 0;
  margin-bottom: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  max-width: 480px;
}
.proj-tab {
  flex: 1;
  padding: 11px 20px;
  font-size: .85rem;
  font-weight: 600;
  letter-spacing: .04em;
  border: none;
  background: transparent;
  color: var(--text-mid);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}
.proj-tab + .proj-tab {
  border-left: 1px solid var(--border);
}
.proj-tab.active {
  background: var(--navy);
  color: var(--white);
}
.proj-tab:not(.active):hover {
  background: var(--bg-alt);
  color: var(--text);
}

/* ── PROJECT CARDS ────────────────────────────────── */
#projects-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.proj-card {
  display: flex;
  align-items: flex-start;
  gap: 28px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 32px;
}
.proj-card-num {
  flex-shrink: 0;
  font-size: 2rem;
  font-weight: 800;
  color: rgba(0,0,0,.12);
  line-height: 1;
  min-width: 40px;
  padding-top: 2px;
}
.proj-card-body { flex: 1; min-width: 0; }
.proj-card-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.5;
  margin-bottom: 14px;
}
.proj-meta {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 4px 20px;
}
.proj-meta dt {
  font-size: .78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .07em;
  color: var(--blue);
  white-space: nowrap;
}
.proj-meta dd {
  font-size: .85rem;
  color: var(--text-mid);
  margin: 0;
}
.proj-empty {
  color: var(--text-lt);
  font-size: .95rem;
  padding: 40px 0;
  text-align: center;
}

/* ── SEMINAR ──────────────────────────────────────────────────── */
.seminar-playlist {
  position: relative;
  width: 100%;
  max-width: 720px;
  margin: 0 auto 48px;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: 0 2px 14px rgba(0,0,0,.06);
}
.seminar-playlist iframe {
  width: 100%;
  height: 100%;
  border: 0;
  display: block;
}

.seminar-year-group { margin-bottom: 36px; }

.seminar-year-label {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--navy);
  padding-bottom: 12px;
  border-bottom: 2px solid var(--gold);
  margin-bottom: 20px;
}

.seminar-item {
  padding: 16px 4px;
  border-bottom: 1px solid var(--border);
}
.seminar-item:last-child { border-bottom: none; }

.seminar-item-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 4px;
}
.seminar-speaker {
  font-size: .95rem;
  font-weight: 600;
  color: var(--text);
}
.seminar-affil {
  font-size: .82rem;
  color: var(--text-mid);
}
.seminar-date {
  font-size: .8rem;
  color: var(--text-lt);
  margin-left: auto;
}
.seminar-title {
  font-size: .9rem;
  color: var(--text-mid);
  line-height: 1.5;
}
.seminar-title a {
  color: var(--blue);
  text-decoration: none;
}
.seminar-title a:hover { text-decoration: underline; }

@media (max-width: 600px) {
  .seminar-date { margin-left: 0; }
}