/* ==========================================================================
   Responsive & Adaptive Stylesheet - 移动端与全平台自适应
   ========================================================================== */

/* --- Laptops & Small Desktops (<= 1200px) --- */
@media (max-width: 1200px) {
  .products-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 22px;
  }
  
  .hero-title {
    font-size: 3rem;
  }
  
  .stats-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
  }
  
  .stat-item:nth-child(3)::after {
    display: none;
  }
  
  .finder-options-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .solutions-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-grid {
    grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
    gap: 30px;
  }
}

/* --- Tablets & Small Laptops (<= 992px) --- */
@media (max-width: 992px) {
  :root {
    --header-height: 68px;
  }

  .nav-menu {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: 100%;
    height: calc(100vh - var(--header-height));
    background: rgba(6, 9, 19, 0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    padding-top: 50px;
    gap: 24px;
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    z-index: 999;
  }

  .nav-menu.mobile-open {
    transform: translateX(0);
  }

  .nav-link {
    font-size: 1.2rem;
  }

  .hamburger-btn {
    display: flex;
  }

  .header-phone-box {
    display: none;
  }

  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-telemetry-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
  }

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

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

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

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

  .rfq-wrapper {
    grid-template-columns: 1fr;
    gap: 40px;
    padding: 32px;
  }

  .rfq-info-box {
    border-left: none;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-left: 0;
    padding-top: 30px;
  }

  .modal-content-grid {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 24px;
  }

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

/* --- Mobile Devices (<= 768px) --- */
@media (max-width: 768px) {
  .section-title {
    font-size: 1.85rem;
  }
  
  .hero-title {
    font-size: 2rem;
  }

  .hero-desc {
    font-size: 1rem;
    margin-bottom: 30px;
  }

  .hero-cta-group {
    flex-direction: column;
    gap: 12px;
  }

  .hero-cta-group .btn {
    width: 100%;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

  .stat-item::after {
    display: none !important;
  }

  .finder-box {
    padding: 24px 16px;
  }

  .finder-options-grid {
    grid-template-columns: 1fr;
  }

  .finder-steps {
    flex-direction: column;
    gap: 14px;
  }

  .step-line {
    display: none;
  }

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

  .search-and-stats {
    flex-direction: column;
    align-items: stretch;
  }

  .search-bar-wrapper {
    max-width: 100%;
  }

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

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

  .form-row {
    grid-template-columns: 1fr;
    gap: 14px;
  }

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

  .footer-bottom {
    flex-direction: column;
    text-align: center;
    gap: 10px;
  }

  .floating-quick-bar {
    right: 14px;
    bottom: 20px;
  }

  .floating-btn {
    width: 42px;
    height: 42px;
  }
}