/* ==========================================================================
   TẮC KÊ SẮT RẸC RẸC - DESIGN SYSTEM & STYLESHEET
   GEO & Performance Optimized CSS
   ========================================================================== */

/* ===== 1. CSS VARIABLES & THEME TOKENS ===== */
:root {
  --primary: #2563eb;
  --primary-rgb: 37, 99, 235;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --primary-subtle: rgba(37, 99, 235, 0.08);
  
  --success: #16a34a;
  --success-bg: rgba(22, 163, 74, 0.08);
  --danger: #dc2626;
  --danger-bg: rgba(220, 38, 38, 0.08);
  --warning: #d97706;
  --warning-bg: rgba(217, 119, 6, 0.1);

  --background: #ffffff;
  --surface: #f8fafc;
  --surface-alt: #f1f5f9;
  --foreground: #0f172a;
  --text-muted: #64748b;
  --text-dim: #94a3b8;
  --border: #e2e8f0;
  --border-subtle: #edf2f7;

  --radius-sm: 0.375rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 25px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 20px 30px -10px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 8px 25px rgba(37, 99, 235, 0.28);

  --font-family: 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== 2. BASE & RESET ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-family);
  scroll-behavior: smooth;
  color: var(--foreground);
  background-color: var(--background);
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

/* ===== 3. LAYOUT & CONTAINERS ===== */
.container {
  width: 100%;
  max-width: 1240px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.25rem;
  padding-right: 1.25rem;
}

.section-spacing {
  padding-top: 5rem;
  padding-bottom: 5rem;
}

@media (max-width: 768px) {
  .section-spacing {
    padding-top: 3.5rem;
    padding-bottom: 3.5rem;
  }
}

/* ===== 4. HEADER & NAV ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow var(--transition-fast);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4.5rem;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.brand-mark {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--primary) 0%, #1d4ed8 100%);
  color: #fff;
  font-weight: 900;
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: center;
  letter-spacing: -0.05em;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
  flex-shrink: 0;
}

.brand-title {
  font-size: 1.125rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.brand-tagline {
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  display: block;
  margin-top: 0.15rem;
}

.main-nav {
  display: none;
  align-items: center;
  gap: 1.75rem;
}

@media (min-width: 768px) {
  .main-nav {
    display: flex;
  }
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--foreground);
  transition: color var(--transition-fast);
  position: relative;
  padding: 0.35rem 0;
}

.nav-link:hover {
  color: var(--primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width var(--transition-fast);
}

.nav-link:hover::after {
  width: 100%;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.55rem 1.15rem;
  border-radius: var(--radius-full);
  background: var(--primary);
  color: #fff;
  font-weight: 700;
  font-size: 0.875rem;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
  transition: all var(--transition-fast);
}

.header-cta:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(37, 99, 235, 0.35);
}

/* ===== 5. BUTTONS & ACTIONS ===== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 0.9rem 1.85rem;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, var(--primary) 0%, #1d4ed8 100%);
  color: #fff;
  font-weight: 700;
  font-size: 1rem;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.35);
  transition: all var(--transition-normal);
  cursor: pointer;
  border: none;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(37, 99, 235, 0.45);
  color: #fff;
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-full);
  border: 2px solid var(--primary);
  background: transparent;
  color: var(--primary);
  font-weight: 700;
  font-size: 0.925rem;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.btn-outline:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.2);
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.95rem;
  transition: color var(--transition-fast);
}

.text-link:hover {
  color: var(--primary);
}

/* ===== 6. HERO SECTION ===== */
.hero-band {
  background: linear-gradient(160deg, #f8fafc 0%, #eff6ff 45%, #ffffff 100%);
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}

.hero-band::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 75% 35%, rgba(37, 99, 235, 0.08) 0%, transparent 60%);
  pointer-events: none;
}

.hero-grid {
  display: grid;
  align-items: center;
  gap: 3rem;
  padding-top: 3.5rem;
  padding-bottom: 4.5rem;
}

@media (min-width: 992px) {
  .hero-grid {
    grid-template-columns: 1.1fr 0.9fr;
    min-height: calc(100vh - 4.5rem);
    padding-top: 2rem;
    padding-bottom: 2rem;
  }
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  border-radius: var(--radius-full);
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary);
  font-weight: 700;
  font-size: 0.825rem;
  letter-spacing: 0.02em;
  margin-bottom: 1.25rem;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -0.03em;
  color: var(--foreground);
  margin-bottom: 1.25rem;
}

.hero-title .highlight {
  background: linear-gradient(135deg, var(--primary) 0%, #1d4ed8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-lead {
  font-size: clamp(1.05rem, 2vw, 1.175rem);
  line-height: 1.7;
  color: var(--text-muted);
  max-width: 38rem;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  margin-bottom: 2.25rem;
}

.proof-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem 2rem;
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
}

.proof-item {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-muted);
}

.proof-item svg {
  color: var(--primary);
  flex-shrink: 0;
}

.hero-media-wrap {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.product-backdrop {
  position: absolute;
  width: 90%;
  height: 90%;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.14) 0%, transparent 70%);
  border-radius: 50%;
  z-index: 0;
}

.hero-image {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 540px;
  filter: drop-shadow(0 15px 30px rgba(0, 0, 0, 0.15));
  transition: transform var(--transition-normal);
}

.hero-image:hover {
  transform: scale(1.02);
}

.floating-spec {
  position: absolute;
  top: 10%;
  right: 2%;
  z-index: 2;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 0.75rem 1.15rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: baseline;
  gap: 0.35rem;
  font-weight: 800;
}

.floating-spec .num {
  font-size: 2.25rem;
  color: var(--primary);
  line-height: 1;
}

.floating-spec small {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.3;
  font-weight: 600;
}

.floating-badge-bottom {
  position: absolute;
  bottom: 8%;
  left: 2%;
  z-index: 2;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 0.6rem 1rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--foreground);
}

.floating-badge-bottom span.dot {
  width: 10px;
  height: 10px;
  background: #22c55e;
  border-radius: 50%;
  box-shadow: 0 0 0 3px rgba(34, 197, 94, 0.2);
}

/* ===== 7. SECTION HEADINGS ===== */
.section-heading {
  text-align: center;
  max-width: 44rem;
  margin: 0 auto 3rem;
}

.section-kicker {
  display: inline-block;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-full);
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary);
  font-weight: 700;
  font-size: 0.8rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 0.85rem;
}

.section-heading h2 {
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--foreground);
  margin-bottom: 0.85rem;
}

.section-heading p {
  color: var(--text-muted);
  font-size: 1.05rem;
  line-height: 1.7;
}

.section-heading.on-dark h2 {
  color: #ffffff;
}

.section-heading.on-dark p {
  color: rgba(255, 255, 255, 0.8);
}

.section-heading.on-dark .section-kicker {
  background: rgba(255, 255, 255, 0.2);
  color: #ffffff;
}

/* ===== 8. GEO ANSWER BLOCK (CITABILITY ENHANCEMENT) ===== */
.answer-block-card {
  background: linear-gradient(135deg, #ffffff 0%, var(--primary-light) 100%);
  border: 2px solid rgba(37, 99, 235, 0.2);
  border-radius: var(--radius-xl);
  padding: 2.25rem;
  margin: 2.5rem 0 3.5rem;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.answer-block-card::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 6px;
  background: var(--primary);
}

.answer-block-header {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 1rem;
}

.answer-badge {
  background: var(--primary);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.answer-block-card h3 {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--foreground);
}

.answer-lead {
  font-size: 1.05rem;
  line-height: 1.75;
  color: #1e293b;
  margin-bottom: 1.25rem;
}

.answer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin-top: 1.25rem;
}

@media (min-width: 768px) {
  .answer-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.answer-stat-box {
  background: rgba(255, 255, 255, 0.85);
  border: 1px solid rgba(37, 99, 235, 0.15);
  border-radius: var(--radius-md);
  padding: 1rem;
}

.answer-stat-box strong {
  display: block;
  font-size: 0.95rem;
  color: var(--primary);
  margin-bottom: 0.25rem;
}

.answer-stat-box p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin: 0;
}

/* ===== 9. COMPARISON SECTION ===== */
.comparison-section {
  background-color: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.comparison-layout {
  display: grid;
  gap: 2.5rem;
  align-items: center;
}

@media (min-width: 992px) {
  .comparison-layout {
    grid-template-columns: 0.9fr 1.1fr;
  }
}

.image-frame {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border);
}

.image-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.comparison-cards-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

@media (min-width: 640px) {
  .comparison-cards-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.comparison-card {
  padding: 1.75rem;
  border-radius: var(--radius-lg);
  background: #ffffff;
  border: 1.5px solid var(--border);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.comparison-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.comparison-card.bad {
  border-color: rgba(220, 38, 38, 0.25);
  background: linear-gradient(180deg, rgba(220, 38, 38, 0.03) 0%, #ffffff 100%);
}

.comparison-card.good {
  border-color: rgba(22, 163, 74, 0.35);
  background: linear-gradient(180deg, rgba(22, 163, 74, 0.04) 0%, #ffffff 100%);
  box-shadow: 0 4px 18px rgba(22, 163, 74, 0.08);
}

.comparison-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  margin-bottom: 0.85rem;
}

.comparison-card.bad .comparison-icon {
  background: var(--danger-bg);
  color: var(--danger);
}

.comparison-card.good .comparison-icon {
  background: var(--success-bg);
  color: var(--success);
}

.comparison-label {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.comparison-card h3 {
  font-size: 1.1rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
  color: var(--foreground);
}

.comparison-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.comparison-list li {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.5;
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
}

.comparison-list li::before {
  content: '•';
  color: currentColor;
  font-weight: bold;
}

/* ===== 10. PRODUCT / SIZE CARDS ===== */
.size-cards-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-top: 2rem;
}

@media (min-width: 768px) {
  .size-cards-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.size-card {
  border-radius: var(--radius-xl);
  border: 1.5px solid var(--border);
  background: #ffffff;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
  display: flex;
  flex-direction: column;
}

.size-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: rgba(37, 99, 235, 0.4);
}

.size-card.featured {
  border-color: rgba(37, 99, 235, 0.5);
  box-shadow: var(--shadow-lg);
  position: relative;
}

.size-card-badge {
  position: absolute;
  top: 1rem;
  right: 1rem;
  z-index: 10;
  background: var(--primary);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-full);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.size-image {
  aspect-ratio: 16/9;
  background: var(--surface);
  overflow: hidden;
  position: relative;
}

.size-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-normal);
}

.size-card:hover .size-image img {
  transform: scale(1.04);
}

.size-content {
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.size-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.5rem;
}

.size-number {
  font-size: 1.6rem;
  font-weight: 900;
  letter-spacing: -0.04em;
  color: var(--foreground);
}

.size-price {
  font-size: 1.35rem;
  font-weight: 900;
  color: var(--primary);
  letter-spacing: -0.02em;
}

.drill-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin-top: 0.5rem;
  margin-bottom: 1rem;
  padding: 0.4rem 0.9rem;
  background: var(--primary-subtle);
  color: var(--primary);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 700;
  width: fit-content;
}

.size-content h3 {
  font-size: 1.15rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: var(--foreground);
}

.size-content p {
  font-size: 0.925rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

/* ===== 11. SPECIFICATIONS TABLE (GEO CRITICAL) ===== */
.specs-table-section {
  background-color: #ffffff;
}

.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-xl);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  background: #ffffff;
  margin-top: 2rem;
}

.specs-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.925rem;
}

.specs-table th, 
.specs-table td {
  padding: 1.1rem 1.25rem;
  border-bottom: 1px solid var(--border);
}

.specs-table thead th {
  background-color: var(--surface);
  font-weight: 800;
  color: var(--foreground);
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.specs-table thead th.col-highlight {
  background-color: var(--primary-light);
  color: var(--primary);
}

.specs-table tbody tr:hover {
  background-color: #f8fafc;
}

.specs-table tbody td.param-name {
  font-weight: 700;
  color: var(--foreground);
  width: 32%;
}

.specs-table tbody td.col-highlight {
  background-color: rgba(37, 99, 235, 0.03);
  font-weight: 600;
  color: #1e3a8a;
}

/* ===== 12. INSTALLATION STEPS (HOW-TO FOR GEO) ===== */
.steps-section {
  background-color: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.steps-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 2.5rem;
}

@media (min-width: 768px) {
  .steps-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .steps-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.step-card {
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  padding: 1.75rem 1.5rem;
  box-shadow: var(--shadow-sm);
  position: relative;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.step-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: rgba(37, 99, 235, 0.3);
}

.step-number {
  width: 2.75rem;
  height: 2.75rem;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, var(--primary) 0%, #1d4ed8 100%);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: 900;
  margin-bottom: 1.15rem;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
}

.step-card h3 {
  font-size: 1.05rem;
  font-weight: 800;
  margin-bottom: 0.6rem;
  color: var(--foreground);
}

.step-card p {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.pro-tip-box {
  margin-top: 2.5rem;
  background: #fffbeb;
  border: 1px solid #fef3c7;
  border-left: 4px solid #f59e0b;
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}

.pro-tip-box svg {
  color: #d97706;
  flex-shrink: 0;
  margin-top: 0.2rem;
}

.pro-tip-box p {
  font-size: 0.925rem;
  color: #92400e;
  line-height: 1.6;
}

/* ===== 13. REVIEWS & TRUST ===== */
.reviews-section {
  background: #ffffff;
}

.review-img-wrap {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  max-width: 960px;
  margin: 0 auto;
  border: 1px solid var(--border);
}

.review-img-wrap img {
  width: 100%;
  height: auto;
}

.trust-strip {
  display: flex;
  gap: 1.5rem 2.5rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--foreground);
}

.trust-item svg {
  color: var(--primary);
}

/* ===== 14. REAL PACKAGING (DARK SECTION) ===== */
.packaging-section {
  background: linear-gradient(135deg, #1e3a8a 0%, #1e40af 50%, #172554 100%);
  color: #ffffff;
}

.real-cards-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-top: 2.5rem;
}

@media (min-width: 768px) {
  .real-cards-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.real-card {
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.18);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.real-image {
  aspect-ratio: 4/3;
  overflow: hidden;
  background: rgba(0, 0, 0, 0.2);
}

.real-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-normal);
}

.real-card:hover .real-image img {
  transform: scale(1.03);
}

.real-card figcaption {
  padding: 1.5rem;
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  color: #ffffff;
}

.real-card figcaption svg {
  flex-shrink: 0;
  color: #93c5fd;
  margin-top: 0.2rem;
}

.real-card strong {
  display: block;
  font-weight: 800;
  font-size: 1.1rem;
  margin-bottom: 0.3rem;
}

.real-card small {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.5;
}

/* ===== 15. FAQ ACCORDION ===== */
.faq-section {
  background-color: var(--surface);
  border-top: 1px solid var(--border);
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  max-width: 820px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: #ffffff;
  transition: box-shadow var(--transition-fast), border-color var(--transition-fast);
}

.faq-item:hover {
  box-shadow: var(--shadow-sm);
  border-color: rgba(37, 99, 235, 0.3);
}

.faq-item summary {
  padding: 1.25rem 1.5rem;
  font-weight: 700;
  font-size: 1.05rem;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  transition: background var(--transition-fast);
  color: var(--foreground);
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary:hover {
  background-color: var(--surface);
}

.faq-item summary::after {
  content: "+";
  font-size: 1.75rem;
  font-weight: 300;
  color: var(--primary);
  transition: transform var(--transition-normal);
  line-height: 1;
}

.faq-item[open] summary::after {
  transform: rotate(45deg);
}

.faq-answer {
  padding: 0 1.5rem 1.35rem;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  margin-top: 0;
  padding-top: 1.1rem;
}

.faq-answer strong {
  color: var(--foreground);
}

/* ===== 16. FINAL CTA & FOOTER ===== */
.final-cta {
  background: linear-gradient(135deg, #eff6ff 0%, #e0e7ff 100%);
  border-top: 1px solid var(--border);
  text-align: center;
}

.cta-icon-circle {
  width: 4rem;
  height: 4rem;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.3);
}

.site-footer {
  background: #ffffff;
  border-top: 1px solid var(--border);
  padding: 3rem 0 2rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.footer-content {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  align-items: center;
  text-align: center;
}

@media (min-width: 768px) {
  .footer-content {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.footer-details strong {
  display: block;
  color: var(--foreground);
  font-size: 1rem;
}

.footer-details small {
  display: block;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* ===== 17. STICKY MOBILE BAR ===== */
.mobile-sticky-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: #ffffff;
  border-top: 1px solid var(--border);
  padding: 0.65rem 1rem;
  display: flex;
  gap: 0.75rem;
  box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.08);
}

@media (min-width: 769px) {
  .mobile-sticky-bar {
    display: none !important;
  }
}

@media (max-width: 768px) {
  body {
    padding-bottom: 4.5rem;
  }
}

.mobile-call-btn {
  flex: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.75rem;
  border-radius: var(--radius-full);
  border: 1.5px solid var(--primary);
  color: var(--primary);
  font-weight: 700;
  font-size: 0.9rem;
  background: #ffffff;
}

.mobile-zalo-btn {
  flex: 2;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.75rem;
  border-radius: var(--radius-full);
  background: var(--primary);
  color: #ffffff;
  font-weight: 700;
  font-size: 0.9rem;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

/* ===== 18. INTERSECTION ANIMATIONS ===== */
.fade-in-on-scroll {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1), transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.fade-in-on-scroll.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Hide Lovable Badge */
#lovable-badge {
  display: none !important;
}