/* ==========================================================================
   RESPONSIVE.CSS - Mobile & Tablet Adaptations
   ========================================================================== */

/* Large Tablets & Desktop Boundaries (1024px) */
@media (max-width: 1024px) {
  .container {
    padding: 0 30px;
  }

  .nav-link {
    padding: 10px 8px !important;
    font-size: 0.8rem !important;
  }

  .megamenu-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
  }

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

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

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

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

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
  }

  .lab-container {
    grid-template-columns: 320px 1fr;
    gap: 25px;
  }

  .lab-viewport {
    height: 520px;
    top: 100px;
  }
}

/* Medium Tablets & Mobiles (768px) */
@media (max-width: 768px) {
  .section-padding {
    padding: 60px 0;
  }

  .top-bar {
    display: none; /* Hide top utility bar on mobile to save space */
  }

  /* Hamburger Menu Toggle Display */
  .hamburger {
    display: block;
  }

  /* Transform Nav Menu to full-screen drawer */
  .nav-menu {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background-color: var(--bg-primary);
    flex-direction: column;
    align-items: flex-start;
    padding: 30px 40px;
    gap: 15px;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    transition: var(--transition-smooth);
    border-top: 1px solid var(--border-color);
  }

  .nav-menu.active {
    left: 0;
  }

  .nav-item {
    width: 100%;
  }

  .nav-link {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
    padding: 12px 60px 12px 20px !important;
    font-size: 1.05rem;
    border-bottom: 1px solid var(--border-color);
  }
  .nav-link i.fa-chevron-down {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%) !important;
    width: 35px;
    height: 35px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    margin: 0 !important;
    font-size: 0.8rem !important;
    transition: transform 0.3s ease, background-color 0.3s ease, color 0.3s ease;
    z-index: 2;
  }
  .nav-link i.fa-chevron-down.rotate-chevron {
    transform: translateY(-50%) rotate(180deg) !important;
    background-color: var(--color-accent);
    color: #ffffff;
    border-color: var(--color-accent);
  }

  /* Disable hover mega menu on mobile - turn into link click or simplify */
  .has-megamenu:hover .megamenu {
    visibility: visible;
    opacity: 1;
    transform: none;
  }

  .megamenu {
    position: static;
    visibility: visible;
    opacity: 1;
    box-shadow: none;
    padding: 10px 0 10px 20px;
    border: none;
    border-left: 2px solid var(--color-accent);
    display: none; /* Controlled via script toggle on click */
    transform: none;
  }

  .megamenu.active {
    display: block;
  }

  .megamenu-grid {
    grid-template-columns: 1fr;
    gap: 15px;
  }

  .megamenu-col h4 {
    margin-bottom: 8px;
    font-size: 0.88rem;
  }

  /* Hero adjustments */
  .hero {
    height: auto;
    padding: 100px 0 80px;
  }

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

  .hero p {
    font-size: 1.05rem;
    margin-bottom: 25px;
  }

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

  .hero-buttons .btn {
    width: 100%;
  }

  /* Stats grid */
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
  }

  .stat-number {
    font-size: 2.5rem;
  }

  /* Lightbox Controls positioning for touch screens */
  .lightbox-prev { left: 10px; }
  .lightbox-next { right: 10px; }

  .lab-container {
    display: flex;
    flex-direction: column-reverse;
    gap: 25px;
  }

  .lab-viewport {
    position: relative;
    top: 0;
    height: 420px;
  }

  .lab-controls {
    padding: 20px;
  }
}

/* Small Mobiles (480px) */
@media (max-width: 480px) {
  .section-title {
    font-size: 1.75rem;
  }

  .section-subtitle {
    font-size: 0.95rem;
    margin-bottom: 30px;
  }

  .services-grid,
  .machinery-grid,
  .industries-grid,
  .footer-grid,
  .why-choose-grid,
  .hero-stats-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .why-choose-item {
    padding: 15px;
  }

  .testimonial-slide {
    padding: 30px 20px;
  }

  .testimonial-quote {
    font-size: 1.05rem;
  }

  .faq-header {
    padding: 15px 20px;
  }

  .faq-header h3 {
    font-size: 0.95rem;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 15px;
    text-align: center;
  }

  .footer-bottom-links {
    justify-content: center;
    width: 100%;
  }

  .whatsapp-float {
    bottom: 20px;
    right: 20px;
    width: 48px;
    height: 48px;
    font-size: 1.5rem;
  }

  .back-to-top {
    bottom: 80px;
    right: 20px;
    width: 38px;
    height: 38px;
    font-size: 1rem;
  }

  .lab-viewport {
    height: 340px;
  }
  
  .annotation-card {
    width: 170px;
    padding: 8px 12px;
    left: 20px;
  }
}