/* ============================================
   响应式布局样式
   ============================================ */

/* --- 平板 (≤1024px) --- */
@media (max-width: 1024px) {
  :root {
    --font-size-base: 17px;
    --font-size-2xl: 32px;
    --font-size-3xl: 38px;
  }

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

  .about-wrapper {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .about-image {
    order: -1;
  }

  .about-img-placeholder {
    max-width: 300px;
  }

  .contact-wrapper {
    grid-template-columns: 1fr;
  }

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

  .product-detail {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .product-detail:nth-child(even) .product-detail-img {
    order: -1;
  }

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

  .cases-page-grid {
    grid-template-columns: 1fr 1fr;
  }
}

/* --- 手机横屏 (≤768px) --- */
@media (max-width: 768px) {
  :root {
    --font-size-base: 16px;
    --font-size-sm: 14px;
    --font-size-lg: 19px;
    --font-size-xl: 22px;
    --font-size-2xl: 26px;
    --font-size-3xl: 32px;
    --header-height: 60px;
  }

  .section {
    padding: 60px 0;
  }

  .section-header {
    margin-bottom: 36px;
  }

  /* 导航 */
  .menu-toggle {
    display: flex;
  }

  .nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--color-white);
    box-shadow: -4px 0 20px rgba(0, 0, 0, 0.1);
    padding: 100px 30px 30px;
    transition: right var(--transition);
    z-index: 1000;
  }

  .nav.open {
    right: 0;
  }

  .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .nav-link {
    font-size: var(--font-size-base);
    padding: 12px 0;
    width: 100%;
  }

  .nav-link::after {
    display: none;
  }

  /* 导航遮罩 */
  .nav-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition);
  }

  .nav-overlay.open {
    opacity: 1;
    visibility: visible;
  }

  .products-grid,
  .cases-grid {
    grid-template-columns: 1fr;
  }

  .hero-title {
    font-size: var(--font-size-2xl);
  }

  .hero-subtitle {
    font-size: var(--font-size-base);
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .hero-actions .btn {
    width: 100%;
    max-width: 240px;
  }

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

  .form-row {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
  }

  /* 子页面 */
  .page-banner {
    min-height: 35vh;
  }

  .product-detail {
    margin-bottom: 40px;
  }

  .cases-page-grid {
    grid-template-columns: 1fr;
  }

  .about-detail-grid {
    grid-template-columns: 1fr;
  }

  .breadcrumb {
    display: none;
  }
}

/* --- 手机竖屏 (≤480px) --- */
@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  .product-card {
    padding: 30px 20px;
  }

  .contact-form {
    padding: 24px;
  }

  .hero-scroll {
    display: none;
  }

  .about-stats {
    gap: 12px;
  }

  .stat-item {
    padding: 14px 8px;
  }
}

/* --- 大屏优化 (≥1400px) --- */
@media (min-width: 1400px) {
  :root {
    --container-width: 1320px;
  }
}