/* ==========================================================================
   RESPONSIVE DESIGN & MOBILE OPTIMIZATIONS
   ========================================================================== */

/* Mobile Navigation Drawer */
.mobile-nav-drawer {
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  height: calc(100vh - var(--header-height));
  height: calc(100dvh - var(--header-height));
  background-color: #ffffff;
  z-index: 99;
  display: none;
  flex-direction: column;
  justify-content: space-between;
  padding: var(--space-6) var(--space-4) var(--space-8);
  gap: var(--space-4);
  transform: translateY(-110%);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: transform 260ms cubic-bezier(0.16, 1, 0.3, 1), opacity 200ms ease, visibility 260ms;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  border-bottom: 1px solid var(--color-border-subtle);
  box-shadow: 0 16px 32px rgba(0, 0, 0, 0.12);
}

.mobile-nav-drawer.active {
  display: flex;
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

@media (min-width: 1025px) {
  .mobile-nav-drawer {
    display: none !important;
    pointer-events: none !important;
  }
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  list-style: none;
  text-align: center;
  padding: 0;
  margin: 0;
}

.mobile-nav-links a {
  display: block;
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-main);
  padding: 0.75rem var(--space-3);
  border-bottom: 1px solid var(--color-border-subtle);
  text-align: center;
  border-radius: var(--radius-xs);
  transition: background-color var(--duration-fast) ease;
}

.mobile-nav-links a:active {
  background-color: var(--color-surface-subtle);
}

.mobile-nav-contact {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding-top: var(--space-4);
  text-align: center;
}

/* ==========================================================================
   TABLET BREAKPOINT (<= 1024px)
   ========================================================================== */
@media (max-width: 1024px) {
  .site-header .nav-links {
    display: none;
  }

  .mobile-menu-btn {
    display: flex;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }

  .card-grid-4,
  .gallery-grid-compact {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
  }

  .card-grid-3 {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
  }

  .card-grid-2,
  .systems-grid-2x2 {
    grid-template-columns: 1fr;
    gap: var(--space-4);
  }

  .efficiency-grid {
    grid-template-columns: 1fr;
    gap: var(--space-6);
  }

  .process-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
  }

  .local-hubs-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-8);
  }
}

/* ==========================================================================
   MOBILE DEVICES (<= 768px)
   ========================================================================== */
@media (max-width: 768px) {
  :root {
    --header-height: 96px;
  }

  .container {
    padding-left: var(--space-4);
    padding-right: var(--space-4);
  }

  .site-header {
    height: var(--header-height);
    padding: 0 var(--space-3);
  }

  .brand-logo-img {
    height: 60px;
    max-height: 64px;
  }

  .brand-logo-text {
    font-size: 1.35rem;
  }

  .site-header .nav-phone {
    display: none;
  }

  .site-header .nav-actions {
    gap: var(--space-2);
  }

  .site-header .nav-actions .btn {
    padding: 0.5rem 0.75rem;
    font-size: var(--font-size-xs);
  }

  /* Accreditation bar on mobile */
  .accreditation-bar {
    padding: var(--space-3) 0;
  }

  .accreditation-grid {
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    text-align: center;
  }

  .accreditation-item {
    font-size: var(--font-size-xs);
    justify-content: center;
    text-align: center;
  }

  /* Hero section on mobile */
  .hero {
    padding-top: var(--space-8);
    padding-bottom: var(--space-10);
    text-align: center;
  }

  .hero-content {
    gap: var(--space-4);
    align-items: center;
    text-align: center;
    margin: 0 auto;
  }

  .hero-title {
    font-size: clamp(1.75rem, 6.5vw, 2.35rem);
    line-height: 1.15;
    letter-spacing: -0.02em;
    text-align: center;
  }

  .hero-subtitle {
    font-size: var(--font-size-base);
    line-height: 1.5;
    text-align: center;
    margin-left: auto;
    margin-right: auto;
  }

  .hero-actions {
    width: 100%;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
  }

  .hero-actions .btn {
    width: 100%;
    max-width: 340px;
  }

  .hero-card {
    padding: var(--space-5);
    border-radius: var(--radius-md);
    text-align: center;
    align-items: center;
  }

  .hero-card-header {
    text-align: center;
    width: 100%;
  }

  .hero-card-header h3 {
    font-size: var(--font-size-lg);
    text-align: center;
  }

  .hero-card .card-specs {
    align-items: center;
    width: 100%;
  }

  .hero-card .card-specs li {
    font-size: var(--font-size-sm);
    justify-content: center;
    text-align: center;
  }

  /* Sections */
  .section {
    padding-top: var(--space-10);
    padding-bottom: var(--space-10);
    text-align: center;
  }

  .section-header {
    margin-bottom: var(--space-6);
    text-align: center;
  }

  .section-header h2 {
    font-size: 1.65rem;
    text-align: center;
  }

  .section-header p {
    text-align: center;
    margin-left: auto;
    margin-right: auto;
  }

  /* Grids */
  .card-grid-4,
  .gallery-grid-compact,
  .card-grid-3,
  .card-grid-2,
  .process-grid,
  .local-hubs-grid {
    grid-template-columns: 1fr;
    gap: var(--space-4);
  }

  .card {
    padding: var(--space-5) !important;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .card-icon-box {
    margin-left: auto;
    margin-right: auto;
  }

  .card h3,
  .card h4,
  .card p {
    text-align: center;
  }

  .card-specs {
    align-items: center;
    width: 100%;
  }

  .card-specs li {
    justify-content: center;
    text-align: center;
  }

  /* About Us Cards on Mobile */
  .about-card {
    text-align: center;
    align-items: center;
  }

  .about-card > div {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  /* Systems Preview Cards on Mobile */
  .system-preview-card {
    text-align: center;
    align-items: center;
  }

  .system-preview-header {
    flex-direction: column-reverse;
    align-items: center;
    gap: var(--space-3);
    margin-bottom: var(--space-3);
    width: 100%;
  }

  .system-preview-header h3 {
    text-align: center;
  }

  .system-preview-header .card-icon-box {
    margin: 0 auto;
  }

  .system-preview-desc {
    text-align: center;
  }

  .system-preview-spec {
    text-align: center;
  }

  .about-card p {
    text-align: center;
  }

  .about-card .btn {
    width: 100%;
    max-width: 340px;
  }

  /* Portfolio & Installation Cards */
  .portfolio-filter-bar,
  .faq-filter-bar {
    display: flex;
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: var(--space-3);
    margin-bottom: var(--space-6);
    justify-content: flex-start;
    gap: var(--space-2);
    scrollbar-width: none;
  }

  .portfolio-filter-bar::-webkit-scrollbar,
  .faq-filter-bar::-webkit-scrollbar {
    display: none;
  }

  .portfolio-filter-btn,
  .faq-filter-btn {
    flex-shrink: 0;
    padding: 0.45rem 0.85rem;
    font-size: var(--font-size-xs);
  }

  .portfolio-card {
    text-align: center;
  }

  .portfolio-body {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .portfolio-body h4 {
    text-align: center;
  }

  .portfolio-specs-list {
    align-items: center;
    width: 100%;
  }

  .portfolio-specs-list li {
    justify-content: center;
    text-align: center;
  }

  /* Process steps */
  .process-step {
    padding: var(--space-5);
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .process-step-num {
    margin-left: auto;
    margin-right: auto;
  }

  .process-step h4,
  .process-step p {
    text-align: center;
  }

  /* Local Service Hubs */
  .local-hub-card {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .local-hub-header {
    flex-direction: column;
    align-items: center;
    text-align: center;
    width: 100%;
    gap: var(--space-2);
  }

  .local-hub-header h4 {
    text-align: center;
  }

  .local-hub-meta {
    align-items: center;
    text-align: center;
    width: 100%;
  }

  .local-hub-card .btn {
    width: 100%;
    max-width: 320px;
  }

  /* Matrix table */
  .matrix-container {
    border-radius: var(--radius-sm);
  }

  .matrix-table th,
  .matrix-table td {
    padding: 0.75rem 0.85rem;
    font-size: var(--font-size-xs);
  }

  /* Area Checker Form */
  .area-checker-box {
    padding: var(--space-5);
    text-align: center;
  }

  .area-checker-box p,
  .area-checker-box h3 {
    text-align: center;
  }

  .area-input-group {
    flex-direction: column;
    gap: var(--space-2);
    align-items: center;
  }

  .area-input-group input,
  .area-input-group button {
    width: 100%;
  }

  /* CTA Banner */
  .section-brand-cyan {
    padding-top: var(--space-10) !important;
    padding-bottom: var(--space-10) !important;
    text-align: center;
  }

  .section-brand-cyan h2,
  .section-brand-cyan p {
    text-align: center;
  }

  .section-brand-cyan .container div:last-child {
    width: 100%;
    flex-direction: column;
    align-items: center;
  }

  .section-brand-cyan .container div:last-child .btn {
    width: 100%;
    max-width: 340px;
  }

  /* Footer */
  .site-footer {
    padding-top: var(--space-10);
    padding-bottom: var(--space-6);
    text-align: center;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-6);
    padding-bottom: var(--space-8);
    text-align: center;
  }

  .footer-col {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .footer-col h4,
  .footer-col p {
    text-align: center;
  }

  .footer-links {
    align-items: center;
    text-align: center;
    padding: 0;
  }

  .footer-contact-item {
    justify-content: center;
    text-align: center;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: var(--space-3);
  }

  /* Modal Dialog */
  .modal-container {
    width: calc(100% - 1.5rem);
    max-height: 92vh;
    padding: var(--space-5);
    border-radius: var(--radius-md);
  }

  .modal-header {
    text-align: center;
  }

  .modal-header h3 {
    text-align: center;
    width: 100%;
  }

  .modal-body {
    padding-top: var(--space-3);
  }

  .modal-body .form-control {
    font-size: 16px; /* Prevents auto-zoom on iOS */
  }
}

/* ==========================================================================
   EXTRA SMALL SCREENS (<= 480px)
   ========================================================================== */
@media (max-width: 480px) {
  .site-header {
    padding: 0 var(--space-2);
  }

  .brand-logo-img {
    height: 52px;
    max-height: 56px;
  }

  .brand-logo-text {
    font-size: 1.15rem;
  }

  .site-header .nav-actions {
    gap: 4px;
  }

  .site-header .nav-actions .btn {
    padding: 0.42rem 0.55rem;
    font-size: 0.78rem;
    letter-spacing: -0.01em;
  }

  .mobile-menu-btn {
    padding: 0.35rem;
  }

  .hero-title {
    font-size: 1.65rem;
  }
}