/* ── Reset & Base ── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: #0a0f1a;
  color: #e8e6e1;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* ── Navigation ── */
nav {
  position: fixed; top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 48px;
  height: 64px;
  background: rgba(10, 15, 26, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255,255,255,0.06);
  transition: transform 0.4s ease;
}
nav.nav-hidden {
  transform: translateY(-100%);
}
.nav-logo {
  display: flex; align-items: center; gap: 12px;
  font-weight: 600; font-size: 1.1rem;
  letter-spacing: 0.02em;
}
.nav-logo img { height: 30px; }
.nav-logo .lab-name {
  color: #888;
  font-weight: 400;
  font-size: 0.85rem;
  letter-spacing: 0.04em;
}
.nav-links { display: flex; gap: 36px; align-items: center; }
.nav-links > a,
.nav-dropdown > .nav-dropdown-toggle {
  font-size: 0.95rem;
  font-weight: 400;
  color: #888;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  transition: color 0.3s;
  position: relative;
  background: none; border: none; cursor: pointer;
  font-family: inherit;
  padding: 0;
}
.nav-links > a:hover,
.nav-links > a.active,
.nav-dropdown:hover > .nav-dropdown-toggle,
.nav-dropdown-toggle.active {
  color: #e8e6e1;
}
.nav-links > a.active::after,
.nav-dropdown-toggle.active::after {
  content: '';
  position: absolute;
  bottom: -4px; left: 0; right: 0;
  height: 1px;
  background: #4a9eff;
}

/* ── Nav Dropdown ── */
.nav-dropdown {
  position: relative;
}
.nav-dropdown-toggle {
  display: flex; align-items: center;
}
.nav-dropdown-menu {
  position: absolute;
  top: calc(100% + 12px);
  left: 50%;
  transform: translateX(-50%);
  background: rgba(10, 15, 26, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 8px;
  padding: 8px 0;
  min-width: 190px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}
.nav-dropdown:hover .nav-dropdown-menu {
  opacity: 1;
  visibility: visible;
}
.nav-dropdown-menu a {
  display: block;
  padding: 10px 24px;
  font-size: 0.9rem;
  white-space: nowrap;
  color: #888;
  letter-spacing: 0.04em;
  transition: color 0.3s, background 0.3s;
  text-transform: uppercase;
}
.nav-dropdown-menu a:hover {
  color: #e8e6e1;
  background: rgba(255,255,255,0.04);
}

/* ── Container ── */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 3rem;
}

/* ── Section Headers ── */
.section-header {
  font-family: 'Playfair Display', Georgia, serif;
  font-size: clamp(1.8rem, 3vw, 2.5rem);
  font-weight: 400;
  margin-bottom: 48px;
  position: relative;
  display: inline-block;
}
.section-header::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 40px;
  height: 2px;
  background: #4a9eff;
}
.section-header a {
  color: inherit;
  transition: color 0.3s;
}
.section-header a:hover {
  color: #4a9eff;
}

/* ── Page Header (subpages) ── */
.page-header {
  padding-top: 140px;
  padding-bottom: 48px;
  text-align: center;
}
.page-header h1 {
  font-family: 'Playfair Display', Georgia, serif;
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 400;
}

/* ── Footer ── */
footer {
  border-top: 1px solid rgba(255,255,255,0.06);
  padding: 32px 48px;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 16px;
}
footer .footer-text {
  text-align: right;
  line-height: 1.7;
  font-size: 0.8rem;
  color: #555;
  letter-spacing: 0.02em;
}

/* ── Scroll Animations ── */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s cubic-bezier(0.23, 1, 0.32, 1),
              transform 0.7s cubic-bezier(0.23, 1, 0.32, 1);
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}
.fade-in-left {
  opacity: 0;
  transform: translateX(-30px);
  transition: opacity 0.7s cubic-bezier(0.23, 1, 0.32, 1),
              transform 0.7s cubic-bezier(0.23, 1, 0.32, 1);
}
.fade-in-left.visible {
  opacity: 1;
  transform: translateX(0);
}
.fade-in-right {
  opacity: 0;
  transform: translateX(30px);
  transition: opacity 0.7s cubic-bezier(0.23, 1, 0.32, 1),
              transform 0.7s cubic-bezier(0.23, 1, 0.32, 1);
}
.fade-in-right.visible {
  opacity: 1;
  transform: translateX(0);
}

/* ── Stagger children ── */
.stagger > *:nth-child(1) { transition-delay: 0s; }
.stagger > *:nth-child(2) { transition-delay: 0.08s; }
.stagger > *:nth-child(3) { transition-delay: 0.16s; }
.stagger > *:nth-child(4) { transition-delay: 0.24s; }
.stagger > *:nth-child(5) { transition-delay: 0.32s; }
.stagger > *:nth-child(6) { transition-delay: 0.4s; }
.stagger > *:nth-child(7) { transition-delay: 0.48s; }
.stagger > *:nth-child(8) { transition-delay: 0.56s; }

/* ── Responsive (shared) ── */
@media (max-width: 768px) {
  nav { padding: 0 24px; }
  .nav-links { gap: 20px; }
  .nav-links a { font-size: 0.75rem; }
  .nav-logo .lab-name { display: none; }
  .container { padding: 0 1.5rem; }
  .page-header { padding-top: 100px; }
  footer { padding: 24px; }
}