.app-header {
  background: var(--card-bg);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  height: 60px;
  width: 100%;
}

.header-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 15px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.main-nav {
  display: flex;
  gap: 1rem;
}

.nav-item {
  padding: 0.5rem 1rem;
  border-radius: var(--border-radius-base);
  color: var(--text-color);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: all 0.2s ease;
}

.nav-item:hover {
  background: var(--lora-surface-hover);
}

.nav-item.active {
  background: var(--lora-primary);
  color: var(--lora-text-on-primary);
}

/* Mobile adjustments */
@media (max-width: 768px) {
  .header-container {
    flex-direction: column;
    padding-top: 0.5rem;
    height: auto;
  }
  
  .app-header {
    height: auto;
  }
  
  .main-nav {
    width: 100%;
    justify-content: center;
    margin-top: 0.5rem;
  }
}