.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(20px);
  background: linear-gradient(to bottom, rgba(7, 8, 9, 0.96), rgba(7, 8, 9, 0.9));
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-4);
  padding-bottom: var(--space-4);
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--color-text);
}

.site-header__logo-mark {
  width: 36px;
  height: 36px;
  border-radius: 40% 60% 50% 50%;
  background: radial-gradient(circle at 30% 20%, rgba(255, 255, 255, 0.45), transparent 55%),
    radial-gradient(circle at 80% 80%, rgba(75, 111, 156, 0.85), transparent 55%),
    var(--color-surface-soft);
  box-shadow: var(--shadow-sm);
}

.site-header__text {
  display: flex;
  flex-direction: column;
}

.site-header__title {
  font-family: var(--font-sans);
  font-size: var(--font-size-lg);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.site-header__subtitle {
  font-size: var(--font-size-xs);
  color: var(--gray-400);
  text-transform: uppercase;
  letter-spacing: 0.15em;
}

.site-header__nav {
  margin-left: auto;
}

.site-header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-header__nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.25rem 0;
  font-size: var(--font-size-sm);
  color: var(--gray-100);
}

.site-header__nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -0.2rem;
  height: 2px;
  border-radius: var(--radius-full);
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  transform-origin: center;
  transform: scaleX(0);
  transition: transform var(--transition-normal);
}

.site-header__nav-link:hover::after,
.site-header__nav-link:focus-visible::after {
  transform: scaleX(1);
}

.site-header__nav-item--cta .site-header__nav-link--cta {
  padding: 0.45rem 1.1rem;
  border-radius: var(--radius-full);
  border: 1px solid rgba(196, 198, 204, 0.32);
  background: radial-gradient(circle at top left, rgba(75, 111, 156, 0.28), transparent 60%),
    rgba(24, 27, 32, 0.96);
  box-shadow: var(--shadow-sm);
}

.site-header__nav-item--cta .site-header__nav-link--cta::after {
  display: none;
}

.site-header__nav-item--cta .site-header__nav-link--cta:hover {
  background: radial-gradient(circle at top left, rgba(75, 111, 156, 0.4), transparent 60%),
    rgba(24, 27, 32, 1);
  border-color: rgba(196, 198, 204, 0.6);
}

.site-header__toggle {
  display: none;
  position: relative;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border-subtle);
  background: rgba(16, 18, 22, 0.96);
  color: var(--color-text);
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

.site-header__toggle-bar {
  position: absolute;
  width: 18px;
  height: 2px;
  border-radius: 999px;
  background-color: var(--gray-100);
  transition: transform var(--transition-normal), opacity var(--transition-normal), top var(--transition-normal), bottom var(--transition-normal);
}

.site-header__toggle-bar:first-child {
  top: 14px;
}

.site-header__toggle-bar:last-child {
  bottom: 14px;
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-bar:first-child {
  top: 19px;
  transform: rotate(45deg);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-bar:last-child {
  bottom: 19px;
  transform: rotate(-45deg);
}

@media (max-width: 864px) {
  .site-header__toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .site-header__nav {
    position: absolute;
    inset-inline: 0;
    top: 100%;
    background: rgba(7, 8, 9, 0.98);
    border-bottom: 1px solid var(--color-border-subtle);
    transform-origin: top;
    transform: scaleY(0.95);
    opacity: 0;
    pointer-events: none;
    visibility: hidden;
    transition: opacity var(--transition-normal), transform var(--transition-normal), visibility var(--transition-normal);
  }

  .site-header__nav-list {
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-4) var(--layout-gutter) var(--space-5);
    gap: var(--space-3);
  }

  .site-header__nav-link {
    width: 100%;
    justify-content: flex-start;
  }

  .site-header__nav-item--cta .site-header__nav-link--cta {
    width: 100%;
    justify-content: center;
    margin-top: var(--space-1);
  }

  .site-header--menu-open .site-header__nav {
    opacity: 1;
    pointer-events: auto;
    visibility: visible;
    transform: scaleY(1);
  }
}

@media (max-width: 520px) {
  .site-header__subtitle {
    display: none;
  }

  .site-header__title {
    font-size: 0.95rem;
  }
}