/* ===== ProJector VN - Modern Design ===== */
@import url('https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:wght@400;500;600;700;800&display=swap');

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

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #eff6ff;
  --accent: #f59e0b;
  --accent-dark: #d97706;
  --dark: #0f172a;
  --text: #1e293b;
  --text-muted: #64748b;
  --bg: #f8fafc;
  --white: #ffffff;
  --border: #e2e8f0;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 4px 20px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 12px 40px rgba(15, 23, 42, 0.12);
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Be Vietnam Pro', -apple-system, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a { text-decoration: none; color: inherit; transition: var(--transition); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ===== HEADER ===== */
html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}
body {
  overflow-x: hidden;
}

.header {
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 200;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  min-height: 56px;
  height: auto;
  padding: 8px 0;
  flex-wrap: nowrap;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 800;
  font-size: clamp(0.95rem, 2.8vw, 1.2rem);
  color: var(--dark);
  flex-shrink: 1;
  min-width: 0;
}
.logo-text {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 42vw;
}

.logo-icon {
  width: clamp(32px, 8vw, 40px);
  height: clamp(32px, 8vw, 40px);
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.35);
  flex-shrink: 0;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-shrink: 0;
}

/* 4 mục chính luôn hiện */
.nav-primary {
  display: flex;
  align-items: center;
  gap: 2px;
  flex-wrap: nowrap;
}

.nav-primary a {
  padding: 7px 10px;
  border-radius: 9px;
  font-weight: 500;
  font-size: clamp(0.72rem, 2.2vw, 0.9rem);
  color: var(--text-muted);
  white-space: nowrap;
}

.nav-primary a:hover { background: var(--primary-light); color: var(--primary); }
.nav-primary a.active { background: var(--primary); color: white; }

/* Nút 3 gạch — luôn hiện */
.menu-toggle {
  display: inline-flex !important;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 10px;
  border: 1.5px solid var(--border);
  background: white;
  font-size: 1.25rem;
  cursor: pointer;
  color: var(--dark);
  padding: 0;
  flex-shrink: 0;
  transition: var(--transition);
  line-height: 1;
}
.menu-toggle:hover,
.menu-toggle.open {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary);
}

/* Panel full menu khi bấm 3 gạch */
.nav-panel {
  display: none;
  border-top: 1px solid var(--border);
  background: white;
  box-shadow: 0 12px 28px rgba(15, 23, 42, 0.1);
  max-height: min(70vh, 480px);
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}
.nav-panel.open { display: block; }

.nav-panel-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 12px 20px 16px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 6px;
}

.nav-panel a {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 14px;
  border-radius: 12px;
  font-weight: 500;
  font-size: 0.92rem;
  color: var(--text);
  background: var(--bg);
  border: 1px solid transparent;
  transition: var(--transition);
}
.nav-panel a:hover {
  background: var(--primary-light);
  color: var(--primary);
  border-color: rgba(37, 99, 235, 0.2);
}
.nav-panel a.active {
  background: var(--primary);
  color: white;
}
.nav-panel a .np-icon { font-size: 1.1rem; }

.nav-panel a.nav-cart { position: relative; }
.nav-cart-badge {
  position: absolute;
  top: 8px;
  right: 10px;
  min-width: 16px;
  height: 16px;
  padding: 0 4px;
  border-radius: 99px;
  background: #ef4444;
  color: white;
  font-size: 0.65rem;
  font-weight: 700;
  display: none;
  align-items: center;
  justify-content: center;
  line-height: 1;
}
.nav-cart-badge.show { display: inline-flex; }

/* tương thích class cũ nếu còn sót */
.nav { display: none; }

/* ===== MOBILE BOTTOM BAR ===== */
.bottom-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 250;
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-top: 1px solid var(--border);
  box-shadow: 0 -4px 20px rgba(15, 23, 42, 0.08);
  padding: 6px 8px calc(6px + env(safe-area-inset-bottom, 0px));
}

.bottom-nav-inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  max-width: 520px;
  margin: 0 auto;
  gap: 4px;
}

.bottom-nav a {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  padding: 8px 4px;
  border-radius: 12px;
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--text-muted);
  text-decoration: none;
  transition: var(--transition);
  position: relative;
}

.bottom-nav a .bn-icon { font-size: 1.25rem; line-height: 1; }
.bottom-nav a.active { color: var(--primary); background: var(--primary-light); }
.bottom-nav a:hover { color: var(--primary); }

.bottom-nav .bn-badge {
  position: absolute;
  top: 4px;
  right: calc(50% - 22px);
  min-width: 16px;
  height: 16px;
  padding: 0 4px;
  border-radius: 99px;
  background: #ef4444;
  color: white;
  font-size: 0.65rem;
  font-weight: 700;
  display: none;
  align-items: center;
  justify-content: center;
}
.bottom-nav .bn-badge.show { display: inline-flex; }

body.has-bottom-nav { padding-bottom: 72px; }

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 28px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  font-family: inherit;
}

.btn-primary {
  background: var(--primary);
  color: white;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}
.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
}

.btn-white {
  background: white;
  color: var(--primary);
  box-shadow: 0 4px 14px rgba(0,0,0,0.1);
}
.btn-white:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,0.15); }

.btn-outline {
  background: transparent;
  color: white;
  border: 2px solid rgba(255,255,255,0.45);
}
.btn-outline:hover { background: rgba(255,255,255,0.12); border-color: white; }

.btn-accent {
  background: var(--accent);
  color: white;
  box-shadow: 0 4px 14px rgba(245, 158, 11, 0.35);
}
.btn-accent:hover { background: var(--accent-dark); transform: translateY(-2px); }

.btn-sm { padding: 9px 18px; font-size: 0.88rem; border-radius: 10px; }
.btn-block { width: 100%; }

/* ===== HERO ===== */
.hero {
  position: relative;
  min-height: 560px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: var(--dark);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, rgba(15,23,42,0.88) 0%, rgba(30,58,138,0.75) 50%, rgba(37,99,235,0.6) 100%),
    url('https://images.unsplash.com/photo-1478720568477-152d9b164e26?w=1600&h=900&fit=crop') center/cover no-repeat;
}

.hero-content {
  position: relative;
  z-index: 2;
  padding: 80px 0;
  max-width: 620px;
  color: white;
}

.hero-badge {
  display: inline-block;
  background: rgba(255,255,255,0.15);
  backdrop-filter: blur(8px);
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 20px;
  border: 1px solid rgba(255,255,255,0.2);
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 18px;
  letter-spacing: -0.02em;
}

.hero p {
  font-size: 1.15rem;
  opacity: 0.9;
  margin-bottom: 36px;
  line-height: 1.7;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; }

/* ===== SECTIONS ===== */
.section { padding: 80px 0; }

.section-header {
  text-align: center;
  margin-bottom: 52px;
}

.section-header .label {
  display: inline-block;
  color: var(--primary);
  font-weight: 600;
  font-size: 0.88rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 10px;
}

.section-header h2 {
  font-size: 2.1rem;
  font-weight: 800;
  color: var(--dark);
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.section-header p {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 520px;
  margin: 0 auto;
}

/* ===== FEATURES ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 32px 26px;
  border: 1px solid var(--border);
  transition: var(--transition);
  text-align: center;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.feature-icon {
  width: 60px;
  height: 60px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin: 0 auto 20px;
}

.fi-blue { background: #dbeafe; }
.fi-green { background: #d1fae5; }
.fi-orange { background: #fef3c7; }
.fi-purple { background: #ede9fe; }

.feature-card h3 {
  font-size: 1.08rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--dark);
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ===== PRODUCT CARDS ===== */
.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.product-card {
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

.product-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.product-img-wrap {
  position: relative;
  height: 200px;
  overflow: hidden;
  background: #f1f5f9;
  display: flex;
  align-items: center;
  justify-content: center;
}

.product-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: contain; /* hiện đủ ảnh, không cắt góc */
  object-position: center;
  transition: transform 0.4s ease;
}

.product-card:hover .product-img-wrap img {
  transform: scale(1.03);
}

.product-badge {
  position: absolute;
  top: 14px;
  left: 14px;
  padding: 5px 12px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 700;
  z-index: 2;
}

.badge-best { background: #fef3c7; color: #b45309; }
.badge-new { background: #d1fae5; color: #047857; }
.badge-hot { background: #fee2e2; color: #b91c1c; }

.product-body {
  padding: 22px 22px 26px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.product-body h3 {
  font-size: 1.12rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 6px;
}

.product-specs {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-bottom: 14px;
}

.product-price {
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--primary);
  margin-top: auto;
  margin-bottom: 16px;
}

/* ===== PAGE HEADER ===== */
.page-header {
  position: relative;
  padding: 70px 0;
  text-align: center;
  color: white;
  overflow: hidden;
}

.page-header-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, rgba(15,23,42,0.85), rgba(37,99,235,0.7)),
    url('https://images.unsplash.com/photo-1593359677879-a4bb92f829d1?w=1400&h=500&fit=crop') center/cover;
}

.page-header .container { position: relative; z-index: 2; }

.page-header h1 {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 10px;
}

.page-header p { opacity: 0.9; font-size: 1.08rem; }

/* ===== FILTER BAR ===== */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 36px;
  justify-content: center;
}

.filter-btn {
  padding: 9px 20px;
  border-radius: 50px;
  border: 1.5px solid var(--border);
  background: white;
  font-weight: 500;
  font-size: 0.9rem;
  cursor: pointer;
  transition: var(--transition);
  font-family: inherit;
  color: var(--text-muted);
}

.filter-btn:hover, .filter-btn.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

/* ===== PRODUCT LIST ===== */
.product-list { display: flex; flex-direction: column; gap: 24px; }

.product-row {
  background: white;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
  display: grid;
  grid-template-columns: 260px 1fr auto;
  transition: var(--transition);
}

.product-row:hover {
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.product-row-img {
  height: 180px;
  overflow: hidden;
  background: #f1f5f9;
  display: flex;
  align-items: center;
  justify-content: center;
}

.product-row-img img {
  width: 100%;
  height: 100%;
  object-fit: contain; /* hiện đủ ảnh, không cắt góc */
  object-position: center;
}

.product-row-body {
  padding: 24px 28px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.product-row-body h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 4px;
}

.product-row-body .meta {
  color: var(--text-muted);
  font-size: 0.88rem;
  margin-bottom: 12px;
}

.specs-tags { display: flex; flex-wrap: wrap; gap: 8px; }

.spec-tag {
  background: var(--bg);
  padding: 4px 12px;
  border-radius: 8px;
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

.product-row-price {
  padding: 24px 28px;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  justify-content: center;
  gap: 12px;
  min-width: 180px;
}

.product-row-price .price {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--primary);
}

/* ===== KNOWLEDGE ===== */
.knowledge-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.knowledge-card {
  background: white;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: var(--transition);
}

.knowledge-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.knowledge-img {
  height: 180px;
  overflow: hidden;
  background: #e2e8f0;
}

.knowledge-img img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  object-position: center;
  background: #f1f5f9;
  transition: transform 0.4s;
}
.knowledge-card:hover .knowledge-img img { transform: scale(1.03); }

.knowledge-body { padding: 24px; }

.knowledge-body .tag {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 8px;
}

.knowledge-body h3 {
  font-size: 1.08rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 10px;
  line-height: 1.4;
}

.knowledge-body p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 16px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.read-more {
  color: var(--primary);
  font-weight: 600;
  font-size: 0.9rem;
}
.read-more:hover { text-decoration: underline; }

/* ===== CALCULATOR ===== */
.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: start;
}

.calc-card {
  background: white;
  border-radius: var(--radius);
  padding: 36px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.calc-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 28px;
}

.form-group { margin-bottom: 20px; }

.form-group label {
  display: block;
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: 8px;
  color: var(--text);
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 13px 16px;
  border: 1.5px solid var(--border);
  border-radius: 12px;
  font-size: 0.95rem;
  font-family: inherit;
  background: var(--bg);
  transition: var(--transition);
  color: var(--text);
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.12);
  background: white;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.result-hero {
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  border-radius: 16px;
  padding: 32px;
  text-align: center;
  color: white;
  margin-bottom: 24px;
}

.result-hero .value {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.1;
}

.result-hero .label {
  font-size: 0.95rem;
  opacity: 0.85;
  margin-top: 6px;
}

.result-list li {
  display: flex;
  justify-content: space-between;
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.95rem;
}

.result-list li:last-child { border-bottom: none; }
.result-list li span:last-child { font-weight: 700; color: var(--dark); }

.screen-preview-box {
  margin-top: 24px;
  background: #0f172a;
  border-radius: 12px;
  padding: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 150px;
}

.screen-preview-box .screen {
  background: linear-gradient(135deg, #1e40af, #3b82f6);
  border: 3px solid #334155;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 0.82rem;
  font-weight: 600;
  transition: all 0.35s ease;
}

/* ===== CONTACT ===== */
.contact-section {
  background: white;
  border-radius: var(--radius);
  padding: 40px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  max-width: 640px;
  margin: 0 auto;
}

.contact-section h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--dark);
}

.contact-section > p {
  color: var(--text-muted);
  margin-bottom: 28px;
}

.alert {
  padding: 14px 18px;
  border-radius: 12px;
  margin-bottom: 20px;
  font-size: 0.92rem;
  font-weight: 500;
  display: none;
}

.alert-success { background: #d1fae5; color: #047857; display: block; }
.alert-error { background: #fee2e2; color: #b91c1c; display: block; }

/* ===== CTA ===== */
.cta-banner {
  background: linear-gradient(135deg, #0f172a, #1e3a8a);
  border-radius: var(--radius);
  padding: 60px 40px;
  text-align: center;
  color: white;
}

.cta-banner h2 {
  font-size: 1.9rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.cta-banner p {
  opacity: 0.85;
  margin-bottom: 28px;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

/* ===== FOOTER ===== */
.footer {
  background: var(--dark);
  color: #94a3b8;
  padding: 60px 0 30px;
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}

.footer h4 {
  color: white;
  font-weight: 700;
  margin-bottom: 18px;
  font-size: 0.95rem;
}

.footer p { font-size: 0.9rem; line-height: 1.7; }
.footer ul li { margin-bottom: 10px; font-size: 0.9rem; }
.footer ul a:hover { color: white; }

.footer-bottom {
  border-top: 1px solid #1e293b;
  padding-top: 24px;
  text-align: center;
  font-size: 0.82rem;
}

/* ===== LOADING ===== */
.loading { text-align: center; padding: 60px; color: var(--text-muted); }

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  margin: 0 auto 16px;
}

@keyframes spin { to { transform: rotate(360deg); } }

/* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .knowledge-grid { grid-template-columns: repeat(2, 1fr); }
  .product-row { grid-template-columns: 200px 1fr; }
  .product-row-price { grid-column: 1 / -1; flex-direction: row; justify-content: space-between; padding-top: 0; }
}

@media (max-width: 900px) {
  .nav-primary a { padding: 6px 8px; }
  .container { padding: 0 14px; }
}

@media (max-width: 768px) {
  .header-inner {
    flex-wrap: nowrap;
    align-items: center;
    padding: 6px 0;
    min-height: 52px;
  }
  .nav-primary a {
    padding: 5px 6px;
    font-size: 0.72rem;
  }
  .menu-toggle {
    width: 38px;
    height: 38px;
    font-size: 1.15rem;
  }
  .nav-panel-inner {
    grid-template-columns: 1fr 1fr;
    padding: 10px 14px 14px;
  }

  .bottom-nav { display: block; }
  body.has-bottom-nav { padding-bottom: 78px; }

  .hero h1 { font-size: clamp(1.5rem, 6vw, 2.1rem); }
  .hero { min-height: auto; }
  .hero-content { padding: 36px 0 44px; }

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

  .calc-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 28px; }
  .product-row { grid-template-columns: 1fr; }
  .product-row-img { height: 180px; }
  .section { padding: 40px 0; }
  .section-header h2 { font-size: clamp(1.25rem, 5vw, 1.7rem); }
  .page-header { padding: 36px 0; }
  .page-header h1 { font-size: clamp(1.35rem, 5.5vw, 2rem); }
  .btn { padding: 11px 18px; font-size: 0.9rem; }
}

@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; }
  .nav-primary a { padding: 4px 5px; font-size: 0.68rem; }
  .logo-text { max-width: 28vw; }
  .nav-panel-inner { grid-template-columns: 1fr; }
  .container { padding: 0 12px; }
  .product-img-wrap { height: 160px; }
}

/* Auth / Cart pages */
.auth-wrap {
  max-width: 440px;
  margin: 0 auto;
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 28px;
  box-shadow: var(--shadow);
}
.auth-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 24px;
}
.auth-tabs button {
  flex: 1;
  padding: 12px;
  border: 1.5px solid var(--border);
  border-radius: 12px;
  background: var(--bg);
  font-family: inherit;
  font-weight: 600;
  cursor: pointer;
  color: var(--text-muted);
  transition: var(--transition);
}
.auth-tabs button.active {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary);
}
.auth-wrap .form-group { margin-bottom: 16px; }
.auth-wrap label {
  display: block;
  font-weight: 600;
  font-size: 0.88rem;
  margin-bottom: 6px;
  color: var(--text);
}
.auth-wrap input {
  width: 100%;
  padding: 12px 14px;
  border: 1.5px solid var(--border);
  border-radius: 12px;
  font-size: 0.95rem;
  font-family: inherit;
  background: var(--bg);
}
.auth-wrap input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.12);
  background: white;
}
.cart-item {
  display: grid;
  grid-template-columns: 88px 1fr auto;
  gap: 16px;
  align-items: center;
  background: white;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px;
  margin-bottom: 12px;
}
.cart-item img {
  width: 88px;
  height: 66px;
  object-fit: contain;
  background: #f1f5f9;
  border-radius: 10px;
}
.cart-item h4 { font-size: 0.98rem; margin-bottom: 4px; color: var(--dark); }
.cart-item .price { color: var(--primary); font-weight: 700; }
.cart-empty { text-align: center; padding: 48px 20px; color: var(--text-muted); }
.account-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  margin-bottom: 20px;
}
.promo-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  background: #fffbeb;
  border: 1px dashed #f59e0b;
  border-radius: 10px;
  font-size: 0.88rem;
  color: #b45309;
  margin: 6px 6px 0 0;
}

/* Utility */
.hidden { display: none !important; }