/* 响应式设计 */
@media (max-width: 1200px) {
  .articles-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .downloads-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 992px) {
  .articles-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .featured-article {
    grid-template-columns: 1fr;
  }

  .downloads-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .hero h1 {
    font-size: 2.5rem;
  }
}

@media (max-width: 768px) {
  .navbar {
    padding: 0.5rem 5%;
  }

  .nav-links-row {
    justify-content: center;
    overflow-x: auto;
    padding: 0.5rem 0;
  }

  .nav-links {
    gap: 0.8rem;
  }

  .nav-links a {
    font-size: 0.9rem;
    padding: 0.4rem 0.6rem;
  }

  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .downloads-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    padding: 2.5rem 5%;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .section-title {
    font-size: 1.6rem;
  }

  .footer-links {
    flex-direction: column;
    gap: 0.8rem;
  }
}

@media (max-width: 576px) {
  .articles-grid {
    grid-template-columns: 1fr;
  }

  .search-bar {
    flex-direction: column;
    border-radius: 12px;
  }

  .search-bar input {
    padding: 1rem;
    width: 100%;
  }

  .search-bar button {
    border-radius: 0;
    padding: 1rem;
  }

  .featured-content {
    padding: 1.5rem;
  }

  .featured-content h2 {
    font-size: 1.5rem;
  }
}