/* Header Layout */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(10, 11, 14, 0.95);
  border-bottom: 1px solid var(--color-border);
  backdrop-filter: blur(10px);
}

.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: var(--color-bg-primary);
  padding: var(--space-2) var(--space-4);
  text-decoration: none;
  z-index: 1000;
  border-radius: 0 0 var(--radius-md) 0;
  font-weight: 600;
  font-size: var(--text-sm);
}

.skip-link:focus {
  top: 0;
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  gap: var(--space-4);
}

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text-primary);
  text-decoration: none;
  flex-shrink: 0;
  letter-spacing: -0.02em;
}

.logo-accent {
  color: var(--color-primary);
  text-shadow: 0 0 20px rgba(0, 212, 255, 0.3);
}

/* Navigation */
.primary-navigation {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  flex: 1;
  justify-content: flex-end;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-link {
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
  font-weight: 500;
  text-decoration: none;
  padding: var(--space-2) 0;
  position: relative;
  transition: color var(--transition-fast);
  white-space: nowrap;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width var(--transition-fast);
  box-shadow: 0 0 10px var(--color-primary);
}

.nav-link:hover,
.nav-link[aria-current="page"] {
  color: var(--color-text-primary);
}

.nav-link:hover::after,
.nav-link[aria-current="page"]::after {
  width: 100%;
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-left: var(--space-6);
  padding-left: var(--space-6);
  border-left: 1px solid var(--color-border);
}

.icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  position: relative;
  text-decoration: none;
}

.icon-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  box-shadow: var(--shadow-neon);
  transform: translateY(-1px);
}

.cart-count {
  position: absolute;
  top: -4px;
  right: -4px;
  background-color: var(--color-primary);
  color: var(--color-bg-primary);
  font-size: var(--text-xs);
  font-weight: 700;
  width: 18px;
  height: 18px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 10px rgba(0, 212, 255, 0.5);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  gap: 5px;
  z-index: 101;
}

.hamburger-line {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--color-text-primary);
  transition: all var(--transition-fast);
  border-radius: 2px;
}

/* Mobile Styles */
@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: flex;
  }

  .primary-navigation {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--color-bg-primary);
    flex-direction: column;
    justify-content: flex-start;
    align-items: flex-start;
    padding: var(--space-6);
    gap: var(--space-8);
    border-top: 1px solid var(--color-border);
    transform: translateX(100%);
    transition: transform var(--transition-slow);
    overflow-y: auto;
  }

  .primary-navigation.is-open {
    transform: translateX(0);
    height: 100vh;
  }

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

  .nav-item {
    width: 100%;
  }

  .nav-link {
    font-size: var(--text-lg);
    padding: var(--space-3) 0;
    display: block;
    width: 100%;
    border-bottom: 1px solid var(--color-border-subtle);
  }

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

  .header-actions {
    margin-left: 0;
    padding-left: 0;
    border-left: none;
    width: 100%;
    justify-content: flex-start;
    gap: var(--space-4);
  }

  .icon-btn {
    width: 48px;
    height: 48px;
    font-size: var(--text-lg);
  }

  /* Hamburger Animation */
  .mobile-menu-toggle[aria-expanded="true"] .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger-line:nth-child(2) {
    opacity: 0;
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }
}

/* Focus Visible */
.mobile-menu-toggle:focus-visible,
.nav-link:focus-visible,
.icon-btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  .primary-navigation {
    transition: none;
  }
}