/* ==========================================================================
   responsive.css — breakpoints (mobile-first; base styles in style.css)
   ≥ 600px  large phones / small tablets
   ≥ 900px  tablets landscape / small desktops
   ≥ 1280px desktop (inline navigation)
   ≥ 1440px large desktop
   ========================================================================== */

/* ---------- ≥ 600px ---------- */
@media (min-width: 600px) {
  :root { --gutter: 28px; --section-y: 80px; }

  .form-grid { grid-template-columns: 1fr 1fr; }
  .form-grid .field-full { grid-column: 1 / -1; }
  .form-grid-3 { grid-template-columns: repeat(3, 1fr); }

  .package-grid { grid-template-columns: 1fr 1fr; }
  .project-grid { grid-template-columns: 1fr 1fr; }
  .product-grid { grid-template-columns: 1fr 1fr; }
  .category-grid { grid-template-columns: repeat(3, 1fr); }
  .stat-band { grid-template-columns: repeat(4, 1fr); }
  .team-grid { grid-template-columns: repeat(4, 1fr); }
  .principles { grid-template-columns: 1fr 1fr; }
  .project-lists { grid-template-columns: 1fr 1fr; }
  .report-kpis { grid-template-columns: repeat(3, 1fr); }
  .report-two { grid-template-columns: 1fr 1fr; }
  .report-actions { grid-template-columns: 1fr 1fr; }
  .product-actions { grid-template-columns: 1fr 1fr; }
  .product-actions .btn { padding-inline: 10px; }
  .solar-report { padding: 28px; }

  .energy-readout dl { grid-template-columns: repeat(4, 1fr); }
  .energy-readout dd { font-size: 1.25rem; }

  .modal-backdrop { align-items: center; padding: 24px; }
  .modal { border-radius: var(--radius-xl); max-height: calc(100vh - 48px); }
  .modal-md { max-width: 620px; }
  .modal-lg { max-width: 1040px; }
  .modal-body { padding: 24px; }

  .contact-form-card { padding: 32px 28px; }
  .calc-block { padding: 24px; }
  .calc-mini { display: none !important; }
  body[data-page="calculator"] .chat-launcher { bottom: calc(14px + env(safe-area-inset-bottom)); }

  /* Chat becomes a floating panel */
  .chat-panel {
    inset: auto 20px 20px auto; width: 420px; height: min(740px, calc(100vh - 40px));
    border-radius: 24px; overflow: hidden; box-shadow: var(--shadow-lg); border: 1px solid var(--line);
  }
  .chat-header { padding-top: 12px; }
  .chat-launcher { right: 20px; bottom: 20px; }
}

/* ---------- ≥ 900px ---------- */
@media (min-width: 900px) {
  :root { --header-h: 72px; --section-y: 96px; }
  body { font-size: 1.0625rem; }

  .hero { padding: 48px 0 88px; }
  .hero-grid { grid-template-columns: 1fr 1.05fr; gap: 48px; }
  .energy-figure { padding-bottom: 40px; }
  .energy-readout { position: absolute; left: -36px; right: 56px; bottom: 0; margin: 0; }

  .section-head-row { flex-direction: row; justify-content: space-between; align-items: flex-end; }

  .split { grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; }
  .benefits-layout { grid-template-columns: 1fr 440px; gap: 64px; align-items: start; }
  .savings-panel { position: sticky; top: calc(var(--header-h) + 24px); padding: 28px; }
  .sizing-factors { grid-template-columns: 1fr 1.6fr; gap: 40px; }

  .steps { grid-template-columns: repeat(3, 1fr); gap: 36px 28px; }
  .steps li { padding: 58px 0 0; }
  .steps li::before { top: 0; }
  .steps li::after { left: 48px; right: -20px; top: 19px; bottom: auto; width: auto; height: 2px; }
  .steps li:nth-child(3n)::after { display: none; }

  .energy-path { grid-template-columns: repeat(5, 1fr); gap: 0; }
  .ep-item { border-radius: 0; padding: 60px 18px 18px; border-right: 1px solid var(--line); }
  .ep-item:first-child { border-radius: var(--radius-md) 0 0 var(--radius-md); }
  .ep-item:last-child { border-radius: 0 var(--radius-md) var(--radius-md) 0; border-right: 0; }
  .ep-item::before { left: 18px; top: 22px; }
  .ep-item:not(:last-child) h3::after { content: ""; }

  .battery-layout { grid-template-columns: 1fr 460px; gap: 64px; align-items: center; }
  .battery-options { grid-template-columns: repeat(3, 1fr); }

  .project-grid { grid-template-columns: repeat(3, 1fr); gap: 24px; }
  .product-grid { grid-template-columns: repeat(3, 1fr); gap: 22px; }
  .category-grid { grid-template-columns: repeat(5, 1fr); }
  .package-grid { grid-template-columns: repeat(4, 1fr); }

  .catalog-toolbar { grid-template-columns: 1fr 280px; align-items: center; }
  .faq-preview { grid-template-columns: 340px 1fr; gap: 56px; align-items: start; }
  .faq-layout { grid-template-columns: 1fr 320px; gap: 40px; }
  .reg-note { position: sticky; top: calc(var(--header-h) + 24px); }
  .help-band { grid-template-columns: 1fr auto; align-items: center; gap: 40px; }
  .cta-inner { grid-template-columns: 1fr auto; align-items: center; gap: 40px; }

  .contact-layout { grid-template-columns: 1fr 1.25fr; gap: 56px; align-items: start; }
  .calc-layout { grid-template-columns: minmax(0, 1fr) 380px; gap: 32px; }
  .calc-results { position: sticky; top: calc(var(--header-h) + 20px); }

  .project-detail { grid-template-columns: 1.15fr 1fr; gap: 32px; align-items: start; }
  .gallery { position: sticky; top: 76px; }

  .footer-grid { grid-template-columns: 1.4fr 1fr 1.2fr 1fr; gap: 40px; }
  .footer-bottom { grid-template-columns: 1fr 1fr; gap: 24px; }
  .footer-bottom p:last-child { text-align: right; }
}

/* ---------- ≥ 1280px: inline navigation ---------- */
@media (min-width: 1280px) {
  .site-header .container { max-width: 1440px; }
  .brand { flex: none; }
  .nav-toggle { display: none; }
  .site-menu {
    position: static; inset: auto; padding: 0; overflow: visible; background: none;
    flex-direction: row; align-items: center; gap: 14px; visibility: visible; opacity: 1; transform: none; transition: none;
  }
  .nav-list { display: flex; gap: 0; }
  .nav-list a {
    padding: 8px 7px; border: 0; border-radius: var(--radius-sm); font-size: .875rem; font-weight: 600;
    color: var(--slate-600); position: relative; white-space: nowrap;
  }
  .nav-list a:hover { color: var(--navy-900); background: var(--surface); }
  .nav-list a[aria-current="page"] { color: var(--navy-900); }
  .nav-list a[aria-current="page"]::after {
    content: ""; position: absolute; left: 7px; right: 7px; bottom: 2px; height: 2px; border-radius: 2px; background: var(--gold-500);
  }
  .header-ctas { display: flex; gap: 8px; }
  .header-survey { display: none; }

}
@media (min-width: 1200px) {
  .hero-grid { grid-template-columns: 1fr 1.1fr; gap: 64px; }
  .package-kw { font-size: 3.8rem; }
}

/* ---------- ≥ 1440px ---------- */
@media (min-width: 1440px) {
  :root { --container: 1320px; }
  .nav-list a { padding-inline: 10px; }
  .hero-title { font-size: 5.4rem; }
}
@media (min-width: 1600px) {
  .header-survey { display: inline-flex; }
}

/* ---------- Small phones ---------- */
@media (max-width: 380px) {
  :root { --gutter: 16px; }
  .brand-name { font-size: .9688rem; }
  .chat-launcher-label { font-size: .875rem; }
  .spec-table > div { grid-template-columns: 1fr; gap: 2px; }
  .report-facts, .kpi-grid { grid-template-columns: 1fr; }
}