/* Header - Option B: Dark & Authoritative */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--color-bg-dark);
  border-bottom: 2px solid var(--color-accent);
  height: var(--header-height);
  transition: box-shadow var(--transition-base);
}

.site-header.is-scrolled {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo img {
  height: 40px;
  width: auto;
}

/* Desktop Nav */
.desktop-nav .nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.desktop-nav .nav-list > li > a {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-2);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-on-dark);
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast);
  white-space: nowrap;
  position: relative;
}

.desktop-nav .nav-list > li > a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: var(--space-3);
  right: var(--space-3);
  height: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.desktop-nav .nav-list > li > a:hover {
  color: var(--color-accent);
}

.desktop-nav .nav-list > li > a:hover::after {
  transform: scaleX(1);
}

.desktop-nav .chevron {
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

/* Nav CTA */
.nav-cta.nav-cta {
  background-color: var(--color-cta);
  color: var(--color-primary) !important;
  padding: var(--space-2) var(--space-5) !important;
  border-radius: var(--radius-md);
  font-weight: 700;
}

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

.nav-cta.nav-cta:hover {
  background-color: var(--color-cta-hover);
  color: var(--color-primary) !important;
}

/* Dropdown */
.desktop-nav .has-dropdown {
  position: relative;
}

.desktop-nav .dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 240px;
  background: var(--color-bg-dark);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: var(--space-2) 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity var(--transition-base), visibility var(--transition-base), transform var(--transition-base);
  z-index: 100;
  border: 1px solid var(--color-border-dark);
}

.desktop-nav .has-dropdown:hover > .dropdown-menu,
.desktop-nav .has-dropdown.is-open > .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.desktop-nav .dropdown-menu a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  color: var(--color-text-on-dark-muted);
  transition: color var(--transition-fast), padding-left var(--transition-fast);
  border-left: 3px solid transparent;
}

.desktop-nav .dropdown-menu a::after {
  display: none;
}

.desktop-nav .dropdown-menu a:hover {
  color: var(--color-accent);
  border-left-color: var(--color-accent);
  padding-left: calc(var(--space-4) + 4px);
}

/* Sub-dropdown (flies right) */
.desktop-nav .dropdown-submenu {
  position: absolute;
  top: 0;
  left: 100%;
  margin-left: 0;
}

.desktop-nav .dropdown-menu .has-dropdown:hover > .dropdown-submenu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  padding: 4px;
  z-index: 1100;
}

.hamburger-line {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-white);
  border-radius: 2px;
  transition: transform var(--transition-base), opacity var(--transition-fast);
}

.hamburger.is-active .hamburger-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger.is-active .hamburger-line:nth-child(2) {
  opacity: 0;
}

.hamburger.is-active .hamburger-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile Nav Overlay */
.mobile-nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  z-index: 1050;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base);
}

.mobile-nav-overlay.is-visible {
  opacity: 1;
  pointer-events: auto;
}

/* Mobile Nav */
.mobile-nav {
  display: none;
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  width: 320px;
  max-width: 85vw;
  background: var(--color-bg-dark);
  z-index: 1060;
  overflow-y: auto;
  padding: calc(var(--header-height) + var(--space-4)) var(--space-4) var(--space-4);
  transform: translateX(100%);
  transition: transform var(--transition-base);
}

.mobile-nav.is-open {
  transform: translateX(0);
}

.mobile-nav-list > li {
  border-bottom: 1px solid var(--color-border-dark);
}

.mobile-nav-list > li > a,
.mobile-dropdown-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: var(--space-3) var(--space-2);
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--color-white);
  text-align: left;
}

.mobile-dropdown-toggle .chevron {
  transition: transform var(--transition-fast);
}

.mobile-nav .has-dropdown.is-open > .mobile-dropdown-toggle .chevron {
  transform: rotate(180deg);
}

.mobile-dropdown-menu {
  display: none;
  padding-left: var(--space-4);
}

.mobile-nav .has-dropdown.is-open > .mobile-dropdown-menu {
  display: block;
}

.mobile-dropdown-menu a {
  display: block;
  padding: var(--space-2) var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-text-on-dark-muted);
}

.mobile-dropdown-menu a:hover {
  color: var(--color-accent);
}

.mobile-nav-cta {
  padding: var(--space-4) var(--space-2);
}

.mobile-nav-cta .btn-primary {
  width: 100%;
  justify-content: center;
}

/* Responsive */
@media (max-width: 1023px) {
  .desktop-nav {
    display: none !important;
  }

  .hamburger,
  .mobile-nav,
  .mobile-nav-overlay {
    display: flex;
  }

  .mobile-nav {
    display: block;
  }

  .mobile-nav-overlay {
    display: block;
  }
}

@media (min-width: 1024px) {
  .hamburger,
  .mobile-nav,
  .mobile-nav-overlay {
    display: none !important;
  }
}

body.nav-open {
  overflow: hidden;
}