/* Header layout and branding */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(16px);
  background-color: rgba(15, 23, 42, 0.88);
  color: #e5e7eb;
  border-bottom: 1px solid rgba(148, 163, 184, 0.35);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.75rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

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

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: inherit;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 0.75rem;
  background: radial-gradient(circle at 10% 0, #38bdf8, #1d4ed8 55%, #020617 100%);
  color: #f9fafb;
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 0.06em;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.03em;
}

.brand-tagline {
  font-size: 0.78rem;
  color: #9ca3af;
}

/* Navigation */
.primary-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.5rem;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 500;
  color: #e5e7eb;
  text-decoration: none;
  letter-spacing: 0.02em;
  transition: color 0.18s ease, background-color 0.18s ease, transform 0.18s ease, box-shadow 0.18s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0.75rem;
  right: 0.75rem;
  bottom: 0.25rem;
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, #38bdf8, #6366f1);
  opacity: 0;
  transform: scaleX(0.5);
  transform-origin: center;
  transition: opacity 0.16s ease, transform 0.16s ease;
}

.nav-link:hover,
.nav-link:focus-visible {
  background-color: rgba(15, 23, 42, 0.85);
  color: #f9fafb;
  outline: none;
  box-shadow: 0 0 0 1px rgba(148, 163, 184, 0.5);
}

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

.nav-link-cta {
  padding-inline: 0.9rem;
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
  color: #f9fafb;
  box-shadow: 0 10px 25px rgba(37, 99, 235, 0.35);
}

.nav-link-cta:hover,
.nav-link-cta:focus-visible {
  background: linear-gradient(135deg, #38bdf8, #818cf8);
  box-shadow: 0 14px 30px rgba(37, 99, 235, 0.45);
}

.nav-link-cta::after {
  display: none;
}

.nav-cta {
  margin-left: 0.25rem;
}

/* Mobile nav toggle */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.35rem;
  border: 1px solid rgba(148, 163, 184, 0.8);
  border-radius: 999px;
  padding: 0.3rem 0.65rem;
  background: rgba(15, 23, 42, 0.95);
  color: #e5e7eb;
  cursor: pointer;
  font-size: 0.85rem;
}

.nav-toggle-box {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.18rem;
}

.nav-toggle-bar {
  width: 1.1rem;
  height: 2px;
  border-radius: 999px;
  background-color: #e5e7eb;
  transition: transform 0.18s ease, opacity 0.18s ease, background-color 0.18s ease;
}

.nav-toggle-text {
  text-transform: uppercase;
  letter-spacing: 0.13em;
}

/* Toggle animated state */
.site-header.menu-open .nav-toggle-bar:nth-child(1) {
  transform: translateY(4px) rotate(42deg);
}

.site-header.menu-open .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}

.site-header.menu-open .nav-toggle-bar:nth-child(3) {
  transform: translateY(-4px) rotate(-42deg);
}

/* Accessibility focus for toggle */
.nav-toggle:focus-visible {
  outline: 2px solid #38bdf8;
  outline-offset: 3px;
}

/* Responsive behavior */
@media (max-width: 768px) {
  .header-inner {
    padding-block: 0.6rem;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .primary-nav {
    position: absolute;
    inset-inline: 0;
    top: 100%;
    background: rgba(15, 23, 42, 0.98);
    border-bottom: 1px solid rgba(148, 163, 184, 0.45);
    transform-origin: top;
    transform: scaleY(0.9);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: opacity 0.18s ease, transform 0.18s ease, visibility 0.18s ease;
  }

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

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    padding: 0.35rem 1.25rem 0.9rem;
  }

  .nav-link,
  .nav-link-cta {
    width: 100%;
    justify-content: space-between;
    padding: 0.6rem 0.8rem;
  }

  .nav-link::after {
    display: none;
  }

  .nav-cta {
    margin-left: 0;
    margin-top: 0.25rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .site-header,
  .primary-nav,
  .nav-link,
  .nav-toggle-bar {
    transition: none !important;
  }
}