.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.65);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color 200ms ease, background-color 200ms ease,
    box-shadow 200ms ease;
}

.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.92);
  border-bottom-color: var(--color-border);
  box-shadow: 0 6px 20px rgba(38, 38, 38, 0.04);
}

.site-header__inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: -0.01em;
  color: var(--brand-ink);
}

.site-header__brand svg {
  height: 26px;
  width: auto;
  color: var(--color-primary);
}

.site-header__nav {
  display: flex;
  align-items: center;
  gap: 32px;
  margin-left: auto;
}

.site-header__nav a {
  color: var(--color-text-muted);
  font-size: 14px;
  font-weight: 500;
  transition: color 120ms ease;
  position: relative;
}

.site-header__nav a:hover,
.site-header__nav a.is-active {
  color: var(--brand-ink);
}

.site-header__nav a::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -6px;
  height: 2px;
  background: var(--color-accent);
  border-radius: 2px;
  opacity: 0;
  transform: scaleX(0.4);
  transition: opacity 160ms ease, transform 160ms ease;
}

.site-header__nav a:hover::after,
.site-header__nav a.is-active::after {
  opacity: 1;
  transform: scaleX(1);
}

.site-header__cta {
  margin-left: 24px;
}

.site-header__burger {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: var(--brand-ink);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--brand-white);
}

@media (max-width: 880px) {
  .site-header__cta {
    display: none;
  }

  .site-header__burger {
    display: inline-flex;
  }

  .site-header__nav {
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--brand-white);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
    padding: 12px 0;
    margin-left: 0;
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: transform 160ms ease, opacity 160ms ease;
  }

  .site-header__nav.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .site-header__nav a {
    padding: 14px 24px;
    font-size: 16px;
    color: var(--brand-ink);
    border-bottom: 1px solid var(--color-border);
  }

  .site-header__nav a::after {
    display: none;
  }
}