/* Header Styles */
.site-header {
  background-color: var(--color-background);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.site-logo h1 {
  margin: 0;
  color: var(--color-primary);
  font-size: var(--font-size-2xl);
  font-weight: 700;
}

.main-nav {
  position: relative;
}

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

.nav-list a {
  color: var(--color-text);
  font-weight: 500;
  padding: var(--space-2) 0;
  transition: color var(--transition-fast);
}

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

.hamburger-btn {
  display: none;
  background: none;
  border: none;
  font-size: var(--font-size-xl);
  color: var(--color-text);
  cursor: pointer;
  padding: var(--space-2);
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.hamburger-btn:hover, .hamburger-btn:focus {
  background-color: var(--color-neutral-100);
  outline: none;
  box-shadow: 0 0 0 2px var(--color-primary);
}

/* Mobile Styles */
@media (max-width: 768px) {
  .hamburger-btn {
    display: block;
  }

  .nav-list {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-background);
    box-shadow: var(--shadow-md);
    flex-direction: column;
    gap: 0;
    padding: var(--space-4);
    transform: translateY(-100%);
    opacity: 0;
    transition: transform var(--transition-normal), opacity var(--transition-normal);
  }

  .nav-list.is-open {
    transform: translateY(0);
    opacity: 1;
  }

  .nav-list a {
    padding: var(--space-3) 0;
    border-bottom: 1px solid var(--color-neutral-200);
  }
}