.zs-header {
  position: sticky;
  top: 0;
  z-index: 40;
  backdrop-filter: blur(14px);
  background: radial-gradient(circle at top, rgba(36, 209, 255, 0.18), transparent 55%),
              linear-gradient(90deg, rgba(5, 7, 11, 0.96), rgba(5, 7, 11, 0.9));
  border-bottom: 1px solid rgba(167, 177, 200, 0.18);
}

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

.zs-header__brand {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.zs-header__logo-link {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-display);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.9rem;
}

.zs-header__logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 10px;
  background: conic-gradient(from 210deg, var(--color-primary), var(--color-accent-orange), var(--color-accent-yellow), var(--color-primary));
  box-shadow: var(--shadow-glow-primary);
  position: relative;
}

.zs-header__logo-mark::after {
  content: "";
  position: absolute;
  inset: 5px;
  border-radius: 8px;
  background: radial-gradient(circle at 30% 10%, rgba(255, 232, 26, 0.6), transparent 55%),
              radial-gradient(circle at 80% 80%, rgba(255, 122, 26, 0.7), transparent 60%),
              #05070b;
}

.zs-header__logo-text {
  font-weight: 600;
}

.zs-header__nav {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

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

.zs-header__nav-link {
  position: relative;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--color-text-muted);
  padding-block: 0.25rem;
}

.zs-header__nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -0.35rem;
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent-orange));
  opacity: 0;
  transform: scaleX(0.3);
  transform-origin: center;
  transition: opacity var(--transition-normal), transform var(--transition-normal);
}

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

.zs-header__nav-link:focus-visible {
  outline: none;
}

.zs-header__cta-wrap {
  margin-left: var(--space-2);
}

.zs-header__cta {
  font-size: 0.75rem;
}

/* Mobile toggle */
.zs-header__toggle {
  display: none;
  position: relative;
  width: 40px;
  height: 32px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-subtle);
  background: rgba(5, 7, 11, 0.9);
  color: var(--color-text);
  justify-content: center;
  align-items: center;
  flex-direction: column;
  gap: 4px;
  cursor: pointer;
}

.zs-header__toggle-line {
  width: 20px;
  height: 2px;
  border-radius: 999px;
  background: var(--color-text);
  transition: transform var(--transition-fast), opacity var(--transition-fast), width var(--transition-fast);
}

.zs-header__toggle:focus-visible {
  outline: 2px solid var(--color-accent-yellow);
  outline-offset: 2px;
}

/* Toggle active state */
.zs-header__toggle[aria-expanded="true"] .zs-header__toggle-line:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.zs-header__toggle[aria-expanded="true"] .zs-header__toggle-line:nth-child(2) {
  opacity: 0;
  width: 0;
}

.zs-header__toggle[aria-expanded="true"] .zs-header__toggle-line:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* Responsive */
@media (max-width: 768px) {
  .zs-header__toggle {
    display: inline-flex;
  }

  .zs-header__nav {
    position: fixed;
    inset-inline: 0;
    top: 56px;
    background: linear-gradient(180deg, rgba(5, 7, 11, 0.97), rgba(5, 7, 11, 0.98));
    border-bottom: 1px solid rgba(167, 177, 200, 0.18);
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-4) var(--space-4) var(--space-6);
    transform: translateY(-120%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition-normal), opacity var(--transition-normal);
  }

  .zs-header__nav-list {
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
    gap: var(--space-2);
  }

  .zs-header__nav-link {
    font-size: 0.85rem;
  }

  .zs-header__cta-wrap {
    width: 100%;
    margin-left: 0;
    margin-top: var(--space-3);
  }

  .zs-header__cta {
    width: 100%;
    justify-content: center;
  }

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

  body.zs-nav-open {
    overflow: hidden;
  }
}

@media (min-width: 769px) {
  .zs-header__nav {
    position: static;
    transform: none !important;
    opacity: 1 !important;
    pointer-events: auto !important;
    padding: 0;
    background: transparent;
    border-bottom: none;
  }
}