/* Header Styles */
.site-header {
  background-color: var(--color-background);
  border-bottom: 1px solid rgba(0,0,0,0.05);
  position: sticky;
  top: 0;
  z-index: 1000;
  padding: var(--space-4) 0;
  transition: box-shadow var(--transition-base);
}

.site-header.scrolled {
  box-shadow: var(--shadow-sm);
  background-color: rgba(250, 250, 248, 0.95);
  backdrop-filter: blur(8px);
}

.brand-logo {
  font-family: var(--font-serif);
  font-size: 1.75rem;
  font-weight: 600;
  color: var(--color-primary);
  letter-spacing: -0.02em;
  z-index: 1001;
}

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

.nav-list {
  list-style: none;
  gap: var(--space-6);
  margin: 0;
  padding: 0;
}

.nav-link {
  font-family: var(--font-sans);
  font-size: var(--size-sm);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-main);
  position: relative;
  padding: 0.5rem 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-secondary);
  transition: width var(--transition-base);
}

.nav-link:hover::after,
.nav-link:focus::after {
  width: 100%;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  z-index: 1001;
}

.hamburger-box {
  width: 24px;
  height: 24px;
  display: inline-block;
  position: relative;
}

.hamburger-inner,
.hamburger-inner::before,
.hamburger-inner::after {
  width: 24px;
  height: 2px;
  background-color: var(--color-text-main);
  border-radius: 2px;
  position: absolute;
  transition: transform 0.15s ease;
}

.hamburger-inner {
  top: 50%;
  transform: translateY(-50%);
}

.hamburger-inner::before {
  content: '';
  top: -8px;
}

.hamburger-inner::after {
  content: '';
  bottom: -8px;
}

/* Mobile Styles */
@media (max-width: 991px) {
  .mobile-menu-toggle {
    display: block;
  }

  .primary-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    max-width: 320px;
    background-color: var(--color-surface);
    padding: var(--space-24) var(--space-6) var(--space-6);
    box-shadow: -5px 0 15px rgba(0,0,0,0.05);
    transform: translateX(100%);
    transition: transform 0.3s ease-in-out;
    visibility: hidden;
    z-index: 1000;
    flex-direction: column;
    align-items: flex-start;
  }

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

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

  .nav-link {
    font-size: var(--size-lg);
    display: block;
    padding: var(--space-2) 0;
  }
  
  .cta-item {
    margin-top: var(--space-4);
    width: 100%;
  }
  
  .cta-item .btn {
    width: 100%;
  }

  /* Hamburger Animation when open */
  .mobile-menu-toggle[aria-expanded="true"] .hamburger-inner {
    background-color: transparent;
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger-inner::before {
    transform: translateY(8px) rotate(45deg);
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger-inner::after {
    transform: translateY(-8px) rotate(-45deg);
  }
  
  /* Overlay for when menu is open */
  body.menu-open::before {
    content: '';
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.3);
    z-index: 999;
    backdrop-filter: blur(2px);
  }
}