/* Header Styles */
.site-header {
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-neutral-200);
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
}

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

.brand {
  display: flex;
  align-items: center;
  text-decoration: none;
  color: var(--color-text);
  z-index: 101;
}

.brand__name {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--font-medium);
  letter-spacing: -0.02em;
}

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

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

.nav-list a {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--color-text);
  text-decoration: none;
  padding: var(--space-2) 0;
  position: relative;
  transition: color var(--duration-fast) var(--ease-out);
}

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

.nav-list a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width var(--duration-normal) var(--ease-out);
}

.nav-list a:hover::after {
  width: 100%;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.icon-btn {
  background: none;
  border: none;
  color: var(--color-text);
  font-size: var(--text-lg);
  cursor: pointer;
  padding: var(--space-2);
  border-radius: var(--radius-full);
  transition: all var(--duration-fast) var(--ease-out);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
}

.icon-btn:hover {
  background-color: var(--color-primary-bg);
  color: var(--color-primary-dark);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
  z-index: 101;
}

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

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  width: 24px;
  height: 2px;
  background-color: var(--color-text);
  left: 0;
  transition: transform var(--duration-normal) var(--ease-out);
}

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

.hamburger::after {
  top: 7px;
}

@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
  }

  .primary-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: var(--color-surface);
    flex-direction: column;
    justify-content: center;
    transform: translateX(-100%);
    transition: transform var(--duration-normal) var(--ease-out);
    z-index: 100;
  }

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

  .nav-list {
    flex-direction: column;
    align-items: center;
    gap: var(--space-6);
  }

  .nav-list a {
    font-size: var(--text-xl);
    font-family: var(--font-heading);
  }

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

  .mobile-menu-toggle[aria-expanded="true"] .hamburger::before {
    transform: translateY(7px) rotate(45deg);
  }

  .mobile-menu-toggle[aria-expanded="true"] .hamburger::after {
    transform: translateY(-7px) rotate(-45deg);
  }

  .header-actions {
    gap: var(--space-2);
  }
}

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