/* ========== 平板及以下 (<992px) ========== */
@media (max-width: 991.98px) {
  .nav-links { display: none; }
  .hamburger { display: flex; }
  .mobile-menu { display: block; }

  .hero-content h1 { font-size: 2.5rem; }
  .products-grid { grid-template-columns: 1fr; gap: 30px; }
  .features-grid { grid-template-columns: repeat(2, 1fr) !important; }
  .scenarios-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .download-content { flex-direction: column; text-align: center; }
  .download-buttons { justify-content: center; }
  .footer-grid { grid-template-columns: 1fr 1fr; }

  .product-hero .container { grid-template-columns: 1fr; text-align: center; }
  .product-hero .image { order: -1; }
  .selling-point .container { grid-template-columns: 1fr; gap: 40px; }
  .selling-point.reverse .container { direction: ltr; }
  .selling-point .sp-image { order: -1; }

  .story-section { grid-template-columns: 1fr; }
  .section-title { font-size: 2rem; }

  .about-hero { padding: 120px 0 60px; }
  .about-hero h1 { font-size: 2.25rem; }
}

/* ========== 手机横屏 (<768px) ========== */
@media (max-width: 767.98px) {
  .hero-content h1 { font-size: 2rem; }
  .hero-content p { font-size: 1rem; }
  .section { padding: 60px 0; }
  .section-title { font-size: 1.75rem; }
  .section-subtitle { font-size: 1rem; margin-bottom: 40px; }

  .features-grid { grid-template-columns: 1fr 1fr !important; gap: 16px; }
  .feature-item { padding: 24px 16px; }
  .scenarios-grid { grid-template-columns: 1fr 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; gap: 30px; }
  .stat-item .number { font-size: 2.25rem; }
  .footer-grid { grid-template-columns: 1fr; }

  .product-hero .text h1 { font-size: 2rem; }
  .selling-point { min-height: auto; padding: 60px 0; }

  .about-hero { padding: 100px 0 50px; }
  .about-hero h1 { font-size: 2rem; }

  .specs-table { overflow-x: auto; -webkit-overflow-scrolling: touch; }
  .specs-table table { min-width: 500px; }
}

/* ========== 手机竖屏 (<576px) ========== */
@media (max-width: 575.98px) {
  :root { --nav-height: 60px; }
  .navbar { padding: 0 20px; }
  .hero-content h1 { font-size: 1.75rem; }
  .hero-buttons { flex-direction: column; align-items: center; }
  .btn { padding: 12px 28px; font-size: 0.9375rem; }

  .features-grid { grid-template-columns: 1fr !important; }
  .scenarios-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; gap: 24px; }

  .product-hero .text h1 { font-size: 1.75rem; }
  .product-hero .text .price { font-size: 1.5rem; }
  .selling-point .sp-text h2 { font-size: 1.5rem; }

  .selling-point .sp-image[style*="grid-template-columns"] {
    grid-template-columns: 1fr !important;
    gap: 8px !important;
  }

  .timeline::before { left: 20px; }
  .timeline-item { flex-direction: row !important; text-align: left !important; padding-left: 50px; }
  .timeline-item .dot { left: 20px; }
  .timeline-item .content { width: 100%; }

  .footer-bottom { flex-direction: column; gap: 12px; text-align: center; }

  .about-hero { padding: 80px 0 40px; }
  .about-hero h1 { font-size: 1.75rem; }
  .about-hero p { font-size: 1rem; }

  .mobile-menu { width: 75vw; max-width: 280px; }
}