/* ============================================================
   DEVILBISS VIETNAM CATALOGUE — DESIGN SYSTEM
   Khung layout giống site Anest Iwata Việt Nam (cùng Nhất Quán JSC).
   Bảng màu: Navy công nghiệp + Đỏ DeVilbiss (biến --flame-* giữ tên cũ
   để các component dùng chung không phải đổi).
   ============================================================ */

:root {
  --navy-950: #071427;
  --navy-900: #0c1f3d;
  --navy-800: #12294f;
  --navy-700: #1a3766;
  --navy-600: #234a86;
  --navy-100: #e7ecf5;
  --navy-50:  #f3f6fb;

  --flame-600: #b3121b;
  --flame-500: #d71920;
  --flame-400: #f0555b;
  --flame-100: #fde4e5;

  --steel-700: #48556b;
  --steel-500: #6b7789;
  --steel-300: #aab3c0;
  --steel-100: #e7eaef;

  --bg: #f6f7fa;
  --surface: #ffffff;
  --text: #16202e;
  --text-muted: #5b6779;
  --border: #e2e6ee;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --shadow-sm: 0 1px 3px rgba(10, 20, 40, 0.08);
  --shadow-md: 0 8px 24px rgba(10, 20, 40, 0.10);
  --shadow-lg: 0 20px 48px rgba(10, 20, 40, 0.16);

  --container: 1240px;
  --font: 'Be Vietnam Pro', 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 26px;
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  cursor: pointer;
  border: 2px solid transparent;
  transition: all 0.18s ease;
}
.btn-primary { background: var(--flame-500); color: #fff; }
.btn-primary:hover { background: var(--flame-600); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-outline { background: transparent; border-color: var(--navy-700); color: var(--navy-800); }
.btn-outline:hover { background: var(--navy-800); color: #fff; }
.btn-ghost-light { background: transparent; border-color: rgba(255,255,255,0.5); color: #fff; }
.btn-ghost-light:hover { background: #fff; color: var(--navy-900); }
.btn-sm { padding: 8px 16px; font-size: 12px; }

/* ---------- Topbar ---------- */
.topbar {
  background: var(--navy-950);
  color: var(--steel-300);
  font-size: 13px;
}
.topbar .container { display: flex; justify-content: space-between; align-items: center; padding-top: 8px; padding-bottom: 8px; }
.topbar a { color: var(--steel-300); }
.topbar a:hover { color: #fff; }
.topbar-links { display: flex; gap: 20px; }
.topbar-links span { color: var(--flame-400); font-weight: 600; }
.topbar-text-mobile { display: none; }

/* ---------- Header ---------- */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; height: 76px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; color: var(--navy-900); }
.logo .mark {
  width: 40px; height: 40px; border-radius: 10px;
  background: linear-gradient(135deg, var(--flame-500), var(--flame-600));
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-weight: 900; font-size: 18px;
}
.logo .brand-sub { display: block; font-size: 11px; font-weight: 600; letter-spacing: 0.08em; color: var(--text-muted); text-transform: uppercase; }

.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
  padding: 10px 16px;
  font-size: 14px;
  font-weight: 600;
  color: var(--navy-800);
  border-radius: var(--radius-sm);
  transition: all 0.15s ease;
}
.main-nav a:hover, .main-nav a.active { background: var(--navy-50); color: var(--flame-600); }

/* ---------- Mega menu (Sản phẩm) ---------- */
.nav-item.has-mega { position: relative; }
.nav-mega-trigger {
  padding: 10px 16px;
  font-size: 14px;
  font-weight: 600;
  color: var(--navy-800);
  border-radius: var(--radius-sm);
  transition: all 0.15s ease;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.nav-mega-trigger:hover, .nav-mega-trigger.active { background: var(--navy-50); color: var(--flame-600); }
.mega-caret { font-size: 10px; transition: transform 0.15s ease; }

.mega-menu {
  position: absolute;
  top: calc(100% + 14px);
  left: 50%;
  transform: translateX(-50%);
  width: min(860px, 94vw);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 28px;
  opacity: 0;
  visibility: hidden;
  transform: translateX(-50%) translateY(8px);
  transition: opacity 0.15s ease, transform 0.15s ease, visibility 0.15s;
  z-index: 200;
}
.nav-item.has-mega:hover .mega-menu,
.nav-item.has-mega.open .mega-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}
.nav-item.has-mega:hover .mega-caret,
.nav-item.has-mega.open .mega-caret { transform: rotate(180deg); }

.mega-menu-inner { display: grid; grid-template-columns: repeat(2, 1fr) 0.9fr; gap: 40px; text-align: left; }
.mega-col-title {
  display: flex; align-items: center; gap: 8px;
  font-size: 14px; font-weight: 800; color: var(--navy-900);
  padding-bottom: 10px; margin-bottom: 10px;
  border-bottom: 2px solid var(--navy-50);
}
.mega-col-title:hover { color: var(--flame-600); }
.mega-ic { font-size: 17px; }
.mega-count { margin-left: auto; font-size: 11px; font-weight: 700; color: var(--text-muted); background: var(--navy-50); padding: 1px 7px; border-radius: 999px; }
.mega-sublist { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 2px; }
.mega-sublist li a {
  display: flex; align-items: center;
  font-size: 13px; color: var(--text-muted); padding: 6px 4px; border-radius: 6px;
}
.mega-sublist li a:hover { background: var(--navy-50); color: var(--flame-600); }
.mega-sublist .mega-count { background: none; padding: 0; }

.mega-col-cta {
  background: var(--navy-50);
  border-radius: var(--radius-md);
  padding: 16px;
  display: flex; flex-direction: column; gap: 10px;
  justify-content: center;
}
.mega-col-cta p { font-size: 13px; font-weight: 700; color: var(--navy-800); margin: 0 0 2px; }
.mega-col-cta .btn { justify-content: center; }

@media (max-width: 1100px) {
  .mega-menu-inner { grid-template-columns: repeat(2, 1fr); }
  .mega-col-cta { grid-column: span 2; flex-direction: row; }
}

.header-cta { display: flex; align-items: center; gap: 12px; }
.icon-btn {
  width: 40px; height: 40px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background: var(--navy-50); color: var(--navy-800);
  border: none; cursor: pointer;
}
.float-call-btn-wrap {
  position: fixed; right: 24px; bottom: 24px; z-index: 300;
  display: flex; flex-direction: column; align-items: flex-end; gap: 12px;
}
.float-zalo-btn {
  width: 52px; height: 52px; border-radius: 50%;
  background: #0068ff; display: flex; align-items: center; justify-content: center;
  box-shadow: var(--shadow-lg); transition: transform 0.18s ease;
}
.float-zalo-btn:hover { transform: translateY(-2px); }
.float-call-btn {
  display: inline-flex; align-items: center; gap: 9px;
  background: linear-gradient(135deg, var(--flame-500), var(--flame-600));
  color: #fff; font-weight: 700; font-size: 15px;
  padding: 14px 22px; border-radius: 999px;
  white-space: nowrap;
  box-shadow: var(--shadow-lg);
  transition: all 0.18s ease;
  animation: aiCallPulse 2.2s ease-in-out infinite;
}
.float-call-btn:hover { filter: brightness(1.08); transform: translateY(-2px); animation-play-state: paused; }
.float-call-btn svg { flex-shrink: 0; }
@keyframes aiCallPulse {
  0%, 100% { box-shadow: var(--shadow-lg), 0 0 0 0 rgba(215,25,32,0.45); }
  50% { box-shadow: var(--shadow-lg), 0 0 0 10px rgba(215,25,32,0); }
}
@media (max-width: 640px) {
  .float-call-btn-wrap { right: 16px; bottom: 16px; }
  .float-call-btn { padding: 12px 18px; font-size: 14px; }
}
.menu-toggle { display: none; }

/* ---------- Hero ---------- */
.hero {
  background: radial-gradient(circle at 20% 20%, var(--navy-700), var(--navy-950) 70%);
  color: #fff;
  padding: 90px 0 100px;
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: "";
  position: absolute; right: -120px; top: -80px;
  width: 480px; height: 480px; border-radius: 50%;
  background: radial-gradient(circle, rgba(215,25,32,0.35), transparent 70%);
}
.hero .container { position: relative; z-index: 2; display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 40px; align-items: center; }
.hero-eyebrow {
  display: inline-block;
  background: rgba(215,25,32,0.16);
  color: var(--flame-400);
  border: 1px solid rgba(215,25,32,0.4);
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 20px;
}
.hero h1 { font-size: 44px; font-weight: 800; line-height: 1.15; margin-bottom: 18px; }
.hero h1 span { color: var(--flame-400); }
.hero p { font-size: 17px; color: var(--steel-300); max-width: 520px; margin-bottom: 30px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-stats { display: flex; gap: 28px; margin-top: 44px; }
.hero-stats div strong { display: block; font-size: 28px; font-weight: 800; color: #fff; }
.hero-stats div span { font-size: 13px; color: var(--steel-300); }
.hero-visual {
  background: #fff;
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--radius-lg);
  padding: 16px;
}
.hero-visual img { border-radius: var(--radius-md); width: 100%; max-height: 600px; object-fit: contain; display: block; margin: 0 auto; }

/* ---------- Section headings ---------- */
.section { padding: 72px 0; }
.section-head { display: flex; justify-content: space-between; align-items: flex-end; margin-bottom: 36px; gap: 20px; flex-wrap: wrap; }
.section-eyebrow { color: var(--flame-600); font-weight: 700; font-size: 13px; letter-spacing: 0.08em; text-transform: uppercase; margin-bottom: 8px; display: block; }
.section-head h2 { font-size: 30px; font-weight: 800; color: var(--navy-900); }
.section-head p { color: var(--text-muted); max-width: 560px; margin-top: 8px; }

/* ---------- Category grid (home) ---------- */
.cat-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 20px; }
.cat-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px 20px;
  text-align: center;
  transition: all 0.2s ease;
}
.cat-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--flame-400); }
.cat-card .cat-icon {
  width: 56px; height: 56px; border-radius: 14px;
  background: var(--navy-50);
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 16px;
  font-size: 26px;
}
.cat-card h3 { font-size: 15px; font-weight: 700; color: var(--navy-900); margin-bottom: 6px; }
.cat-card span { font-size: 12px; color: var(--text-muted); }

/* ---------- Product grid ---------- */
.product-toolbar {
  display: flex; gap: 14px; align-items: center; flex-wrap: wrap;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-md); padding: 16px 20px; margin-bottom: 24px;
}
.search-box { flex: 1; min-width: 220px; position: relative; }
.search-box input {
  width: 100%; padding: 11px 16px 11px 40px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); font-size: 14px; font-family: var(--font);
}
.search-box::before { content: "🔍"; position: absolute; left: 14px; top: 50%; transform: translateY(-50%); opacity: 0.5; }
.result-count { font-size: 13px; color: var(--text-muted); white-space: nowrap; }

.tab-row { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 14px; }
.tab-chip {
  padding: 9px 18px; border-radius: 999px; font-size: 13px; font-weight: 600;
  background: var(--navy-50); color: var(--navy-800); cursor: pointer; border: 1px solid transparent;
}
.tab-chip.active { background: var(--navy-900); color: #fff; }
.subcat-row { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 30px; }
.subcat-chip {
  padding: 6px 14px; border-radius: 999px; font-size: 12px; font-weight: 600;
  background: var(--flame-100); color: var(--flame-600); cursor: pointer; border: 1px solid transparent;
}
.subcat-chip.active { background: var(--flame-500); color: #fff; }

.product-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.product-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: all 0.2s ease;
}
.product-card:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); border-color: var(--navy-600); }
.product-card .thumb {
  height: 220px; overflow: hidden; background: #fff; border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center; padding: 18px;
  position: relative;
}
.product-card .thumb img { width: 100%; height: 100%; object-fit: contain; }
.product-card .cat-tag {
  position: absolute; top: 10px; left: 10px;
  background: var(--navy-900); color: #fff; font-size: 10px; font-weight: 700;
  padding: 4px 10px; border-radius: 999px; text-transform: uppercase; letter-spacing: 0.04em;
}
.product-card .body { padding: 18px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.product-card h3 { font-size: 15px; font-weight: 700; color: var(--navy-900); }
.product-card p { font-size: 13px; color: var(--text-muted); flex: 1; }
.product-card .card-foot { display: flex; justify-content: space-between; align-items: center; margin-top: 8px; }
.link-arrow { font-size: 13px; font-weight: 700; color: var(--flame-600); }
.link-arrow:hover { text-decoration: underline; }

.empty-state { text-align: center; padding: 60px 20px; color: var(--text-muted); }

.img-broken img { display: none; }
.img-broken::after { content: "Ảnh đang cập nhật"; font-size: 12px; color: var(--text-muted); }
.pd-image.img-broken::after { content: "Ảnh sản phẩm đang cập nhật"; }

/* ---------- Product detail ---------- */
.breadcrumb { font-size: 13px; color: var(--text-muted); margin-bottom: 24px; }
.breadcrumb a:hover { color: var(--flame-600); }
.pd-grid { display: grid; grid-template-columns: 0.9fr 1.1fr; gap: 50px; margin-bottom: 60px; }
.pd-image { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 40px; display: flex; align-items: center; justify-content: center; min-height: 380px; }
.pd-image img { max-height: 360px; }
.pd-info .cat-tag-lg { display: inline-block; background: var(--flame-100); color: var(--flame-600); font-size: 12px; font-weight: 700; padding: 5px 14px; border-radius: 999px; text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 14px; }
.pd-info h1 { font-size: 32px; font-weight: 800; color: var(--navy-900); margin-bottom: 14px; }
.pd-info .lead { color: var(--text-muted); font-size: 15px; margin-bottom: 24px; }
.pd-info .actions { display: flex; gap: 12px; margin-bottom: 30px; }
.feature-list { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.feature-list li { display: flex; gap: 10px; align-items: flex-start; font-size: 14px; background: var(--navy-50); padding: 12px 14px; border-radius: var(--radius-sm); }
.feature-list .emoji { font-size: 18px; }

.tabs { display: flex; gap: 6px; border-bottom: 2px solid var(--border); margin-bottom: 30px; }
.tab-btn { padding: 12px 22px; font-weight: 700; font-size: 14px; color: var(--text-muted); cursor: pointer; border-bottom: 3px solid transparent; margin-bottom: -2px; }
.tab-btn.active { color: var(--navy-900); border-color: var(--flame-500); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

.spec-table { width: 100%; border-collapse: collapse; background: var(--surface); border-radius: var(--radius-md); overflow: hidden; border: 1px solid var(--border); }
.spec-table tr:nth-child(even) { background: var(--navy-50); }
.spec-table td { padding: 13px 20px; font-size: 14px; }
.spec-table td:first-child { font-weight: 700; color: var(--navy-800); width: 40%; }

.app-list { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.app-list li { background: var(--navy-900); color: #fff; font-size: 13px; padding: 8px 16px; border-radius: 999px; }

.why-box { background: linear-gradient(135deg, var(--navy-900), var(--navy-700)); color: #fff; padding: 30px 34px; border-radius: var(--radius-lg); margin-top: 20px; }
.why-box h4 { font-size: 13px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--flame-400); margin-bottom: 10px; }

/* ---------- Contact form ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1.2fr; gap: 28px; align-items: start; }
.contact-grid .why-box { margin-top: 0; max-width: none; }
.contact-form { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 28px; box-shadow: var(--shadow-sm); }
.cf-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.cf-field { margin-bottom: 16px; }
.cf-field label { display: block; font-size: 13px; font-weight: 700; margin-bottom: 6px; color: var(--navy-800); }
.cf-field input, .cf-field textarea {
  width: 100%; padding: 11px 14px; border: 1px solid var(--border); border-radius: var(--radius-sm);
  font-family: inherit; font-size: 14px; background: var(--bg);
}
.cf-field input:focus, .cf-field textarea:focus { outline: none; border-color: var(--flame-500); background: var(--surface); }
.contact-form .btn { width: 100%; justify-content: center; }
.cf-status { margin-top: 14px; font-size: 13px; font-weight: 600; min-height: 18px; }
.cf-status.cf-success { color: #1a7f37; }
.cf-status.cf-error { color: #c0392b; }
@media (max-width: 860px) {
  .contact-grid { grid-template-columns: 1fr; }
  .cf-row { grid-template-columns: 1fr; }
}

/* ---------- Quote request modal (trang san pham) ---------- */
.quote-modal-backdrop { display: none; position: fixed; inset: 0; background: rgba(7,20,39,0.55); z-index: 400; align-items: flex-start; justify-content: center; overflow-y: auto; padding: 40px 16px; }
.quote-modal-backdrop.open { display: flex; }
.quote-modal { background: var(--surface); border-radius: var(--radius-lg); padding: 28px 32px; max-width: 480px; width: 100%; }
.quote-modal h3 { font-size: 18px; font-weight: 800; color: var(--navy-900); margin-bottom: 6px; }
.quote-modal .qf-product { font-size: 13px; color: var(--text-muted); margin-bottom: 18px; }
.quote-modal .qf-product strong { color: var(--navy-800); }
.quote-modal-actions { display: flex; gap: 10px; margin-top: 4px; }

.why-us { display: grid; grid-template-columns: repeat(4,1fr); gap: 20px; margin-top: 30px; }
.why-us .item { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-md); padding: 24px; text-align: center; }
.why-us .item .ic { font-size: 28px; margin-bottom: 10px; }
.why-us .item h4 { font-size: 14px; font-weight: 700; margin-bottom: 6px; color: var(--navy-900); }
.why-us .item p { font-size: 12px; color: var(--text-muted); }

.company-why { background: linear-gradient(135deg, var(--flame-500), var(--flame-600)); color: #fff; padding: 32px 36px; border-radius: var(--radius-lg); margin-top: 30px; }
.company-why h3 { font-size: 18px; font-weight: 800; margin-bottom: 16px; }
.company-why-list { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2,1fr); gap: 10px 24px; }
.company-why-list li { font-size: 14px; line-height: 1.5; }
.company-why-contact { margin-top: 20px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,0.25); }
.company-why-contact h4 { font-size: 13px; text-transform: uppercase; letter-spacing: 0.06em; opacity: 0.85; margin-bottom: 10px; }
.company-why-contact p { font-size: 15px; font-weight: 700; display: flex; align-items: center; flex-wrap: wrap; gap: 10px 14px; margin: 0 0 6px; }
.company-why-contact a { color: #fff; text-decoration: underline; }
.zalo-link { display: inline-flex; align-items: center; gap: 7px; background: rgba(255,255,255,0.18); padding: 7px 14px 7px 8px; border-radius: 999px; text-decoration: none !important; font-size: 14px; }
.zalo-link:hover { background: rgba(255,255,255,0.3); }
.zalo-link svg { flex-shrink: 0; }
@media (max-width: 640px) { .company-why-list { grid-template-columns: 1fr; } }

.related-title { font-size: 22px; font-weight: 800; color: var(--navy-900); margin-bottom: 20px; }

/* ---------- Footer ---------- */
.site-footer { background: var(--navy-950); color: var(--steel-300); padding: 60px 0 24px; margin-top: 40px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1.2fr; gap: 40px; margin-bottom: 40px; }
.footer-grid h4 { color: #fff; font-size: 14px; margin-bottom: 16px; text-transform: uppercase; letter-spacing: 0.06em; }
.footer-grid ul li { margin-bottom: 10px; font-size: 14px; }
.footer-grid a:hover { color: var(--flame-400); }
.footer-brand p { font-size: 13px; margin: 14px 0; max-width: 300px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); padding-top: 20px; display: flex; justify-content: space-between; font-size: 12px; flex-wrap: wrap; gap: 10px; }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .product-grid { grid-template-columns: repeat(3, 1fr); }
  .cat-grid { grid-template-columns: repeat(3, 1fr); }
  .why-us { grid-template-columns: repeat(2,1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .pd-grid { grid-template-columns: 1fr; }
}
@media (max-width: 768px) {
  .nav-toggle { display: flex; }
  .header-cta { display: none; }
  .main-nav {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--surface); border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md); padding: 8px 16px 16px;
  }
  .site-header.nav-open .main-nav { display: flex; }
  .main-nav > a, .nav-mega-trigger { padding: 12px 8px; border-bottom: 1px solid var(--border); border-radius: 0; }
  .mega-menu {
    position: static; transform: none; width: auto; box-shadow: none; border: none;
    padding: 8px 0 8px 12px; display: none; opacity: 1; visibility: visible;
  }
  .nav-item.has-mega:hover .mega-menu { transform: none; }
  .nav-item.has-mega.open .mega-menu { display: block; transform: none; }
  .mega-menu-inner { grid-template-columns: 1fr; gap: 16px; }
  .mega-col-cta { grid-column: auto; flex-direction: column; }
  .topbar-text-desktop { display: none; }
  .topbar-text-mobile { display: block; }
  .topbar-links { display: none; }
  .logo .mark { display: none; }
  .logo { font-size: 15px; white-space: nowrap; }
  .hero { padding: 50px 0 40px; }
  .hero .container { grid-template-columns: 1fr; }
  .hero h1 { font-size: 32px; }
  .hero-stats { margin-top: 28px; gap: 18px; }
  .hero-visual { display: none; }
  .product-grid { grid-template-columns: repeat(2, 1fr); }
  .cat-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-list { grid-template-columns: 1fr; }
  .why-us { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
}

/* ---------- Mobile nav toggle ---------- */
.nav-toggle {
  display: none; flex-direction: column; justify-content: center; gap: 5px;
  width: 44px; height: 44px; padding: 10px; border: none; border-radius: var(--radius-sm);
  background: var(--navy-50); cursor: pointer;
}
.nav-toggle span { display: block; height: 2px; background: var(--navy-900); border-radius: 2px; transition: transform 0.2s ease, opacity 0.2s ease; }
.site-header.nav-open .nav-toggle span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.site-header.nav-open .nav-toggle span:nth-child(2) { opacity: 0; }
.site-header.nav-open .nav-toggle span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero (DeVilbiss) ---------- */
.hero-visual { position: relative; }
.hero-visual .hero-caption {
  position: absolute; left: 16px; right: 16px; bottom: 16px;
  background: var(--navy-900); color: #fff; border-radius: var(--radius-md);
  padding: 12px 16px; display: flex; justify-content: space-between; align-items: center; gap: 12px;
  font-size: 13px;
}
.hero-visual .hero-caption strong { font-size: 15px; }
.hero-visual .hero-caption a { color: var(--flame-400); font-weight: 700; white-space: nowrap; }
.hero-visual img { max-height: 460px; padding-bottom: 84px; }

/* ---------- Nhóm sản phẩm (trang chủ) ---------- */
.group-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.group-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-md);
  overflow: hidden; display: flex; flex-direction: column; transition: all 0.2s ease;
}
.group-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--flame-400); }
.group-card .thumb { height: 190px; overflow: hidden; background: #fff; display: flex; align-items: center; justify-content: center; padding: 16px; border-bottom: 1px solid var(--border); }
.group-card .thumb img { width: 100%; height: 100%; object-fit: contain; }
.group-card-cta { background: linear-gradient(135deg, var(--navy-900), var(--navy-700)); border-color: transparent; justify-content: flex-end; }
.group-card-cta .body { padding: 26px 22px; }
.group-card.group-card-cta h3 { color: #fff; font-size: 19px; margin: 8px 0 14px; }
.group-card.group-card-cta .group-parent, .group-card.group-card-cta .link-arrow { color: var(--flame-400); }
.group-card .body { padding: 16px 18px; }
.group-card .group-parent { font-size: 11px; font-weight: 700; letter-spacing: 0.06em; text-transform: uppercase; color: var(--flame-600); }
.group-card h3 { font-size: 16px; font-weight: 700; color: var(--navy-900); margin: 4px 0 2px; }
.group-card span.count { font-size: 12px; color: var(--text-muted); }

/* ---------- Dải công nghệ phun ---------- */
.tech-strip { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.tech-card { background: var(--navy-900); color: var(--steel-300); border-radius: var(--radius-md); padding: 26px; }
.tech-card .tech-tag { display: inline-block; font-size: 12px; font-weight: 800; letter-spacing: 0.08em; color: #fff; background: var(--flame-500); padding: 4px 10px; border-radius: 999px; margin-bottom: 12px; }
.tech-card h3 { color: #fff; font-size: 17px; margin-bottom: 8px; }
.tech-card p { font-size: 14px; }

@media (max-width: 1024px) {
  .group-grid { grid-template-columns: repeat(2, 1fr); }
  .tech-strip { grid-template-columns: 1fr; }
}
@media (max-width: 480px) {
  .group-grid { grid-template-columns: 1fr 1fr; gap: 12px; }
  .group-card .body { padding: 12px; }
  .group-card h3 { font-size: 14px; }
  .product-grid { grid-template-columns: 1fr 1fr; gap: 12px; }
  .product-card .body { padding: 12px; }
  .product-card h3 { font-size: 14px; }
  .hero-stats { flex-wrap: wrap; }
}

@media (max-width: 480px) {
  .product-card .thumb { height: 150px; padding: 12px; }
  .group-card .thumb { height: 130px; padding: 10px; }
}
@media (max-width: 768px) {
  .nav-toggle { display: flex; }
}
.main-nav .btn-primary, .main-nav .btn-primary:hover { color: #fff; }
.main-nav .btn-outline:hover { color: #fff; }
@media (max-width: 768px) {
  .nav-mega-trigger { display: flex; width: 100%; }
}