/* Header Base */
.site-header {
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-neutral-200);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

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

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  text-decoration: none;
  flex-shrink: 0;
  z-index: 9999;
}

.logo-text {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: -0.02em;
  transition: color var(--transition-fast);
}

.site-logo:hover .logo-text {
  color: var(--color-accent);
}

/* Navigation */
.main-nav {
  display: flex;
  align-items: center;
  justify-content: center;
}

.nav-list {
  display: flex;
  list-style: none;
  gap: var(--space-8);
  margin: 0;
  padding: 0;
}

.nav-list a {
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text);
  text-decoration: none;
  padding: var(--space-2) 0;
  position: relative;
  transition: color var(--transition-fast);
}

.nav-list a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--transition-base);
}

.nav-list a:hover,
.nav-list a:focus {
  color: var(--color-accent);
}

.nav-list a:hover::after,
.nav-list a:focus::after {
  transform: scaleX(1);
  transform-origin: left;
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-md);
  color: var(--color-text);
  text-decoration: none;
  transition: all var(--transition-fast);
  position: relative;
  background: transparent;
  border: none;
  cursor: pointer;
}

.icon-btn:hover,
.icon-btn:focus {
  background-color: var(--color-neutral-100);
  color: var(--color-accent);
}

.cart-count {
  position: absolute;
  top: 0;
  right: 0;
  background-color: var(--color-accent);
  color: white;
  font-size: var(--text-xs);
  font-weight: 700;
  width: 1.25rem;
  height: 1.25rem;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  transform: translate(25%, -25%);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
  margin-left: auto;
  z-index: 1001;
  color: var(--color-primary);
  transition: color var(--transition-fast);
}

.mobile-menu-toggle:hover,
.mobile-menu-toggle:focus {
  color: var(--color-accent);
}

.hamburger {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-primary);
  position: relative;
  transition: background-color var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 2px;
  background-color: var(--color-primary);
  left: 0;
  transition: transform var(--transition-base);
}

.hamburger::before {
  top: -7px;
}

.hamburger::after {
  bottom: -7px;
}

/* Mobile Styles */
@media (max-width: 768px) {
  .header-container {
    height: auto;
    padding: var(--space-3) 0;
  }

  .mobile-menu-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .main-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--color-bg);
    flex-direction: column;
    justify-content: flex-start;
    padding: 5rem var(--space-4) var(--space-8);
    transform: translateX(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    align-items: stretch;
    z-index: 1000;
    overflow-y: auto;
  }

  .main-nav.is-open {
    transform: translateX(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-list {
    flex-direction: column;
    gap: var(--space-4);
    width: 100%;
  }

  .nav-list a {
    font-size: var(--text-xl);
    display: block;
    padding: var(--space-3) 0;
  }

  .nav-list a::after {
    display: none;
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger {
    background-color: transparent;
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger::before {
    transform: rotate(45deg);
    top: 0;
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger::after {
    transform: rotate(-45deg);
    bottom: 0;
  }

  .header-actions {
    gap: var(--space-1);
  }
}