.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  backdrop-filter: blur(18px);
  background: linear-gradient(to bottom, rgba(10, 35, 28, 0.96), rgba(12, 15, 14, 0.88));
  border-bottom: 1px solid var(--color-border-subtle);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding-block: var(--space-3);
}

.site-header__branding {
  display: flex;
  align-items: center;
}

.site-header__brand-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
}

.site-header__logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 40% 60% 55% 45%;
  background: radial-gradient(circle at 30% 0%, #6ee7b7, #0f766e);
  box-shadow: 0 0 0 1px rgba(148, 163, 184, 0.55), var(--shadow-soft);
}

.site-header__title {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--color-text);
}

.site-header__subtitle {
  display: none;
  font-size: var(--font-size-xs);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

.site-header__nav {
  display: flex;
  align-items: center;
}

.site-header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  font-size: var(--font-size-xs);
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.site-header__nav-link {
  position: relative;
  padding-block: 0.35rem;
  color: var(--gray-300);
  text-decoration: none;
}

.site-header__nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--color-primary), transparent);
  transition: width var(--transition-base);
}

.site-header__nav-link:hover,
.site-header__nav-link:focus-visible {
  color: var(--color-text);
}

.site-header__nav-link:hover::after,
.site-header__nav-link:focus-visible::after {
  width: 100%;
}

.site-header__nav-item--accent .site-header__nav-link--cta {
  padding-inline: 1rem;
  padding-block: 0.4rem;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(45, 212, 191, 0.7);
  background: radial-gradient(circle at 0 0, rgba(110, 231, 183, 0.18), rgba(12, 10, 9, 0.3));
  color: var(--color-primary-soft);
}

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

.site-header__nav-item--accent .site-header__nav-link--cta:hover,
.site-header__nav-item--accent .site-header__nav-link--cta:focus-visible {
  border-color: rgba(110, 231, 183, 0.95);
  background: radial-gradient(circle at 0 0, rgba(110, 231, 183, 0.28), rgba(15, 23, 42, 0.9));
  color: var(--gray-50);
}

.nav-toggle {
  flex-direction: column;
  gap: 4px;
  width: 40px;
  height: 40px;
  border-radius: 999px;
  border: 1px solid rgba(148, 163, 184, 0.5);
  background: rgba(15, 23, 42, 0.9);
  color: var(--gray-200);
}

.nav-toggle__bar {
  width: 18px;
  height: 1px;
  border-radius: 999px;
  background: var(--gray-200);
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.nav-toggle--open .nav-toggle__bar:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.nav-toggle--open .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle--open .nav-toggle__bar:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

@media (max-width: 899px) {
  .site-header__subtitle {
    display: none;
  }

  .site-header__nav {
    position: fixed;
    inset-inline: 0;
    top: 64px;
    background: linear-gradient(to bottom, rgba(10, 35, 28, 0.98), rgba(12, 15, 14, 0.98));
    border-bottom: 1px solid var(--color-border-subtle);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: transform var(--transition-base), opacity var(--transition-base), visibility var(--transition-base);
  }

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

  .site-header__nav-link {
    font-size: var(--font-size-sm);
  }

  .site-header__nav--open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
}

@media (min-width: 900px) {
  .nav-toggle {
    display: none;
  }

  .site-header__subtitle {
    display: inline-block;
  }
}