header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 28px 56px;
  border-bottom: 1px solid transparent;
  transition:
    background 0.4s ease,
    backdrop-filter 0.4s ease,
    border-color 0.4s ease;
}
.nav.scrolled {
  background: rgba(5, 8, 16, 0.72);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom-color: var(--line-soft);
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
}
.brand-mark {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: radial-gradient(
    circle at 35% 35%,
    var(--gold-hi),
    var(--gold) 45%,
    var(--gold-deep) 85%
  );
  box-shadow:
    0 0 18px rgba(217, 168, 90, 0.6),
    0 0 40px rgba(217, 168, 90, 0.25);
  position: relative;
  flex-shrink: 0;
}
.brand-mark::after {
  content: '';
  position: absolute;
  inset: -6px;
  border-radius: 50%;
  border: 1px solid rgba(217, 168, 90, 0.35);
}
.brand-text {
  font-family: var(--serif);
  letter-spacing: 0.06em;
  font-size: 22px;
  font-weight: 500;
}
.brand-text .lab {
  color: var(--gold);
}

.nav-links {
  display: flex;
  gap: 44px;
  list-style: none;
  font-size: 13px;
  letter-spacing: 0.22em;
  font-weight: 500;
  color: var(--ink-dim);
}
.nav-links a {
  position: relative;
  padding: 6px 0;
  transition: color 0.3s;
}
.nav-links a:hover {
  color: var(--ink);
}
.nav-links a.active {
  color: var(--ink);
}
.nav-links a.active::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 1px;
  background: var(--gold);
}