#nav {
  position: fixed;
  top: 16px;
  left: 50%;
  transform: translateX(-50%);
  width: calc(100% - 48px);
  max-width: 1200px;
  z-index: 1000;
  background: var(--glass);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid rgba(255,255,255,0.5);
  border-radius: 100px;
  padding: 12px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all 0.4s ease;
  box-shadow: var(--shadow-sm), inset 0 1px 0 rgba(255,255,255,0.6);
}
#nav.scrolled {
  padding: 9px 24px;
  background: rgba(255,255,255,0.88);
  box-shadow: var(--shadow-md);
}
.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
}
.nav-brand-logos {
  display: flex;
  align-items: center;
  gap: 6px;
}
.nav-logo {
  width: 36px;
  height: 36px;
  border-radius: 6px;
  overflow: hidden;
  background: var(--csi-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.65rem;
  font-weight: 800;
  color: white;
  letter-spacing: 0.05em;
  flex-shrink: 0;
}
.nav-logo-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}
.nav-logo-griet { background: #fff; }
.nav-brand-text { display: flex; flex-direction: column; }
.nav-brand-name {
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.1;
}
.nav-brand-sub {
  font-size: 0.65rem;
  color: var(--muted);
  font-weight: 400;
}
.nav-divider {
  width: 1px;
  height: 16px;
  background: var(--border-strong);
  margin: 0 4px;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-link {
  padding: 7px 14px;
  border-radius: 100px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--ink);
  transition: all 0.25s ease;
  cursor: pointer;
  position: relative;
}
.nav-link:hover, .nav-link.active {
  background: var(--csi-light-blue);
  color: var(--csi-accent);
}
.nav-cta {
  background: var(--ink);
  color: var(--white) !important;
  border-radius: 100px;
  padding: 8px 18px !important;
  font-size: 0.825rem !important;
  font-weight: 600 !important;
}
.nav-cta:hover {
  background: var(--csi-blue) !important;
  color: var(--white) !important;
}
.nav-hamburger {
  display: none;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--csi-light-blue);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  border: none;
  position: relative;
  transition: background 0.25s ease;
}
.nav-hamburger span {
  display: block;
  width: 16px;
  height: 1.5px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-hamburger.open {
  background: rgba(10,36,99,0.12);
}
.nav-hamburger.open span:nth-child(1) {
  transform: translateY(6.5px) rotate(45deg);
}
.nav-hamburger.open span:nth-child(2) {
  opacity: 0;
}
.nav-hamburger.open span:nth-child(3) {
  transform: translateY(-6.5px) rotate(-45deg);
}


body.menu-open { overflow: hidden; }


#mobile-menu {
  display: flex;
  position: fixed;
  inset: 0;
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(24px);
  z-index: 999;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  
  opacity: 0;
  pointer-events: none;
  transform: translateY(-12px);
  transition: opacity 0.25s ease, transform 0.25s ease;
}
#mobile-menu.open {
  opacity: 1;
  pointer-events: all;
  transform: translateY(0);
}
#mobile-menu .nav-link {
  font-size: 1.5rem;
  font-family: var(--font-display);
  font-weight: 700;
  padding: 12px 24px;
}


.mobile-close-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  padding: 12px 28px;
  font-size: 0.95rem;
  font-weight: 600;
  font-family: var(--font-body);
  color: var(--ink);
  background: rgba(10,36,99,0.08);
  border: none;
  border-radius: 100px;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.2s ease;
}
.mobile-close-btn:hover {
  background: rgba(10,36,99,0.16);
  transform: translateY(-1px);
}
.mobile-close-btn:active { transform: translateY(0); }