/* ==========================================================================
   TAS LOYALTY - CYBER-NEXUS & AI FINTECH DESIGN SYSTEM (2026)
   Theme: Deep Space Cyber (#050811), Teal/Cyan & Radiant Gold/Orange Neon
   ========================================================================== */

:root {
  /* Brand Deep Space Backgrounds - ZERO PLAIN WHITE */
  --bg-body: #050811;
  --bg-surface: #090e1e;
  --bg-surface-elevated: #0e162f;
  --bg-surface-glass: rgba(10, 16, 34, 0.82);
  --bg-surface-card: rgba(13, 21, 44, 0.76);
  --bg-surface-dark: #03050a;

  /* Primary Holographic Cyan / Teal Gradient */
  --teal-dark: #0A9473;
  --teal-main: #10B5B0;
  --cyan-bright: #2BD2E4;
  --cyan-glow: rgba(43, 210, 228, 0.45);
  --teal-glow: rgba(16, 181, 176, 0.35);
  --teal-subtle: rgba(16, 181, 176, 0.12);

  /* Accent Radiant Gold / Orange Gradient */
  --gold-light: #FCD255;
  --orange-main: #F48B28;
  --orange-dark: #DF6122;
  --orange-glow: rgba(244, 139, 40, 0.45);
  --orange-subtle: rgba(244, 139, 40, 0.12);

  /* Contrast Text Hierarchy */
  --text-bright: #FFFFFF;
  --text-main: #F8FAFC;
  --text-muted: #94A3B8;
  --text-subtle: #64748B;

  /* Cyber Borders & Luminescent Dividers */
  --border-subtle: rgba(43, 210, 228, 0.15);
  --border-strong: rgba(43, 210, 228, 0.32);
  --border-glass: rgba(255, 255, 255, 0.08);
  --border-orange: rgba(244, 139, 40, 0.28);
  --border-glow: rgba(43, 210, 228, 0.55);

  /* Cyber Shadows & Glows */
  --shadow-sm: 0 2px 6px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 6px 18px rgba(0, 0, 0, 0.55);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.7);
  --shadow-glow-cyan: 0 0 30px rgba(43, 210, 228, 0.22);
  --shadow-glow-orange: 0 0 30px rgba(244, 139, 40, 0.22);

  /* Dimensions & Geometry */
  --container-max-w: 1240px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 30px;
  --radius-full: 9999px;
  --header-h: 78px;

  /* Typography */
  --font-sans: "Plus Jakarta Sans", "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: "Space Grotesk", "Plus Jakarta Sans", sans-serif;
  --font-mono: "JetBrains Mono", monospace;
}

/* ==========================================================================
   CSS Reset & Base Theme
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-body);
  color: var(--text-main);
}

body.cyber-dark-theme {
  font-family: var(--font-sans);
  background-color: var(--bg-body);
  color: var(--text-main);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  position: relative;
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
  transition: all 0.25s ease;
}

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

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
}

.container {
  width: 100%;
  max-width: var(--container-max-w);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
  position: relative;
  z-index: 1;
}

/* ==========================================================================
   Typography & Holographic Utilities
   ========================================================================== */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--text-bright);
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.gradient-teal, .gradient-cyan {
  background: linear-gradient(135deg, #10B5B0 0%, #2BD2E4 50%, #A5F3FC 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.gradient-orange, .gradient-gold {
  background: linear-gradient(135deg, #FCD255 0%, #F48B28 50%, #DF6122 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.gradient-title-white {
  background: linear-gradient(135deg, #FFFFFF 40%, #2BD2E4 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.text-cyan { color: var(--cyan-bright); }
.text-teal { color: var(--teal-main); }
.text-orange { color: var(--orange-main); }
.text-gold { color: var(--gold-light); }
.text-muted { color: var(--text-muted); }
.text-mono { font-family: var(--font-mono); }

/* Badges */
.badge-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  font-family: var(--font-mono);
  line-height: 1;
}

.badge-cyan-glow {
  background: rgba(43, 210, 228, 0.12);
  color: var(--cyan-bright);
  border: 1px solid rgba(43, 210, 228, 0.35);
  box-shadow: 0 0 15px rgba(43, 210, 228, 0.2);
}

.badge-orange-glow {
  background: rgba(244, 139, 40, 0.12);
  color: var(--gold-light);
  border: 1px solid rgba(244, 139, 40, 0.35);
  box-shadow: 0 0 15px rgba(244, 139, 40, 0.2);
}

.pill-glow-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--cyan-bright);
  box-shadow: 0 0 8px var(--cyan-bright);
  animation: radarPing 2s infinite;
}

.pill-glow-dot-orange {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--orange-main);
  box-shadow: 0 0 8px var(--orange-main);
  animation: radarPingOrange 2s infinite;
}

/* ==========================================================================
   Cyber Button System
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 24px;
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: 0.94rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-decoration: none;
  user-select: none;
  position: relative;
  overflow: hidden;
  line-height: 1;
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.85rem;
}

.btn-lg {
  padding: 15px 32px;
  font-size: 1.05rem;
}

/* Primary Button: Radiant Orange Gradient */
.btn-primary, .btn-orange {
  background: linear-gradient(135deg, #F48B28 0%, #DF6122 100%);
  color: #FFFFFF;
  box-shadow: 0 4px 18px rgba(244, 139, 40, 0.45), inset 0 1px 1px rgba(255, 255, 255, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.btn-primary:hover, .btn-orange:hover {
  background: linear-gradient(135deg, #FCD255 0%, #F48B28 100%);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(244, 139, 40, 0.6), 0 0 20px rgba(252, 210, 85, 0.3);
  color: #FFFFFF;
}

/* Secondary Button: Holographic Cyan Gradient */
.btn-cyan, .btn-teal {
  background: linear-gradient(135deg, #0A9473 0%, #10B5B0 50%, #2BD2E4 100%);
  color: #FFFFFF;
  box-shadow: 0 4px 18px rgba(16, 181, 176, 0.4), inset 0 1px 1px rgba(255, 255, 255, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.btn-cyan:hover, .btn-teal:hover {
  background: linear-gradient(135deg, #10B5B0 0%, #2BD2E4 100%);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(43, 210, 228, 0.55), 0 0 20px rgba(43, 210, 228, 0.35);
  color: #FFFFFF;
}

/* Outline Cyan Button */
.btn-outline-cyan, .btn-outline-teal {
  background: rgba(43, 210, 228, 0.06);
  color: var(--cyan-bright);
  border: 1.5px solid rgba(43, 210, 228, 0.35);
  backdrop-filter: blur(10px);
}

.btn-outline-cyan:hover, .btn-outline-teal:hover {
  background: rgba(43, 210, 228, 0.15);
  border-color: var(--cyan-bright);
  color: #FFFFFF;
  transform: translateY(-2px);
  box-shadow: 0 0 20px rgba(43, 210, 228, 0.25);
}

/* Outline Dark Glass Button */
.btn-outline-white {
  background: rgba(255, 255, 255, 0.05);
  color: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.14);
  backdrop-filter: blur(8px);
}

.btn-outline-white:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: var(--cyan-bright);
  color: #FFFFFF;
  transform: translateY(-2px);
  box-shadow: 0 0 16px rgba(43, 210, 228, 0.2);
}

.btn-glow {
  position: relative;
  overflow: hidden;
}

.btn-glow::after {
  content: "";
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(60deg, transparent, rgba(255, 255, 255, 0.22), transparent);
  transform: rotate(30deg);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.btn-glow:hover::after {
  opacity: 1;
  animation: shimmerSweep 1.5s infinite;
}

/* ==========================================================================
   Header & Cyber Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-h);
  background: rgba(5, 8, 17, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(43, 210, 228, 0.14);
  z-index: 1000;
  transition: all 0.3s ease;
}

.site-header.scrolled {
  background: rgba(5, 8, 17, 0.95);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.7);
  border-bottom-color: rgba(43, 210, 228, 0.25);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: 1360px;
  width: 100%;
  margin: 0 auto;
  padding: 0 24px;
  gap: 16px;
}

.brand-wrapper {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  flex-shrink: 0;
}

.logo-box-glow {
  position: relative;
  border-radius: var(--radius-sm);
  padding: 3px;
  background: linear-gradient(135deg, rgba(43, 210, 228, 0.4), rgba(244, 139, 40, 0.3));
  box-shadow: 0 0 16px rgba(43, 210, 228, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
}

.brand-logo-img {
  height: 40px;
  width: auto;
  object-fit: contain;
  display: block;
  filter: drop-shadow(0 2px 8px rgba(0, 0, 0, 0.5));
}

.brand-info h1 {
  font-size: 1.18rem;
  font-weight: 800;
  color: #FFFFFF;
  line-height: 1.1;
  letter-spacing: -0.01em;
  margin: 0;
}

.brand-tagline {
  font-size: 0.72rem;
  color: var(--cyan-bright);
  font-family: var(--font-mono);
  font-weight: 600;
  letter-spacing: 0.04em;
  display: block;
  margin-top: 2px;
}

/* AI Status Live Beacon */
.ai-live-beacon {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 6px 12px;
  background: rgba(10, 16, 34, 0.65);
  border: 1px solid rgba(43, 210, 228, 0.25);
  border-radius: var(--radius-full);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--cyan-bright);
  letter-spacing: 0.05em;
  user-select: none;
  flex-shrink: 0;
}

.beacon-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--cyan-bright);
  box-shadow: 0 0 8px var(--cyan-bright);
  animation: radarPing 2s infinite;
  display: inline-block;
  flex-shrink: 0;
}

/* Desktop Nav - Non-squeezing Flex items */
.desktop-nav {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}

.desktop-nav .nav-link {
  padding: 8px 16px;
  font-size: 0.93rem;
  font-weight: 600;
  color: var(--text-muted);
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
  position: relative;
  text-decoration: none;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
}

.desktop-nav .nav-link:hover {
  color: #FFFFFF;
  background: rgba(43, 210, 228, 0.08);
}

.desktop-nav .nav-link.active {
  color: var(--cyan-bright);
  font-weight: 700;
  background: rgba(43, 210, 228, 0.08);
}

.desktop-nav .nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 14px;
  right: 14px;
  height: 2px;
  background: linear-gradient(90deg, #10B5B0, #2BD2E4);
  box-shadow: 0 0 10px #2BD2E4;
  border-radius: 2px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

/* Mobile Toggle */
.mobile-toggle-btn {
  display: none;
  background: transparent;
  border: none;
  color: #FFFFFF;
  padding: 8px;
  cursor: pointer;
}

/* Mobile Drawer */
.mobile-drawer-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(3, 5, 10, 0.85);
  backdrop-filter: blur(8px);
  z-index: 1050;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

.mobile-drawer-backdrop.active {
  opacity: 1;
  visibility: visible;
}

.mobile-drawer {
  position: fixed;
  top: 0;
  right: -320px;
  width: 300px;
  height: 100%;
  background: #080D1C;
  border-left: 1px solid var(--border-subtle);
  z-index: 1100;
  padding: 24px;
  display: flex;
  flex-direction: column;
  transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: -10px 0 40px rgba(0, 0, 0, 0.8);
}

.mobile-drawer.active {
  transform: translateX(-320px);
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 18px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.drawer-close-btn {
  background: transparent;
  border: none;
  font-size: 26px;
  cursor: pointer;
  color: var(--text-muted);
}

.drawer-nav {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 24px;
}

.drawer-nav a {
  padding: 12px 16px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
}

.drawer-nav a.active, .drawer-nav a:hover {
  background: rgba(43, 210, 228, 0.1);
  color: var(--cyan-bright);
}

/* ==========================================================================
   Cyber Card & Bento Grid System
   ========================================================================== */
.cyber-card, .tech-card, .bento-card {
  background: var(--bg-surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  position: relative;
  overflow: hidden;
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: var(--shadow-sm);
}

.cyber-card:hover, .tech-card:hover, .bento-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-strong);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.7), 0 0 25px rgba(43, 210, 228, 0.15);
}

/* Card Spotlight Hover Effect */
.card-spotlight {
  position: relative;
}

.card-spotlight::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(450px circle at var(--mouse-x, -500px) var(--mouse-y, -500px), rgba(43, 210, 228, 0.15), transparent 65%);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.3s;
  border-radius: inherit;
}

.card-spotlight:hover::before {
  opacity: 1;
}

/* Top Laser Line on Cards */
.cyber-card::after {
  content: "";
  position: absolute;
  top: 0;
  left: 20%;
  right: 20%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(43, 210, 228, 0.7), transparent);
  opacity: 0.6;
}

/* ==========================================================================
   HERO SECTION: Cyber Cockpit & Fintech HUD
   ========================================================================== */
.hero-section {
  position: relative;
  padding: 80px 0 100px;
  overflow: hidden;
}

.hero-grid-pattern {
  position: absolute;
  inset: 0;
  background-image: 
    radial-gradient(circle at 50% 15%, rgba(43, 210, 228, 0.15) 0%, transparent 60%),
    linear-gradient(rgba(43, 210, 228, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(43, 210, 228, 0.05) 1px, transparent 1px);
  background-size: 100% 100%, 48px 48px, 48px 48px;
  pointer-events: none;
  z-index: 1;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.95fr;
  align-items: center;
  gap: 48px;
  position: relative;
  z-index: 2;
}

.hero-title {
  font-size: clamp(2.6rem, 4.5vw, 3.8rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 22px;
}

.hero-desc {
  font-size: 1.15rem;
  line-height: 1.75;
  color: var(--text-muted);
  margin-bottom: 34px;
  max-width: 580px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 38px;
}

/* Hero Stats Strip */
.hero-trust-indicators {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  padding-top: 28px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.trust-item {
  background: rgba(10, 16, 34, 0.5);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-md);
  padding: 12px 16px;
}

.trust-number {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 800;
  line-height: 1;
}

.trust-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 6px;
  font-family: var(--font-mono);
}

/* Interactive Hero Cockpit Terminal */
.hero-cockpit {
  background: rgba(10, 16, 34, 0.88);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid rgba(43, 210, 228, 0.3);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: 0 30px 70px -15px rgba(0, 0, 0, 0.85), 0 0 35px rgba(43, 210, 228, 0.15);
  position: relative;
}

.cockpit-tabs-header {
  display: flex;
  gap: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 14px;
  margin-bottom: 18px;
}

.cockpit-tab-btn {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 7px 14px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s ease;
}

.cockpit-tab-btn:hover {
  color: #FFFFFF;
  background: rgba(255, 255, 255, 0.05);
}

.cockpit-tab-btn.active {
  background: rgba(43, 210, 228, 0.15);
  color: var(--cyan-bright);
  border-color: rgba(43, 210, 228, 0.35);
  box-shadow: 0 0 12px rgba(43, 210, 228, 0.2);
}

.cockpit-status-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
}

.cockpit-metrics-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 18px;
}

.cockpit-metric-card {
  background: rgba(14, 22, 44, 0.75);
  border: 1px solid rgba(43, 210, 228, 0.18);
  border-radius: var(--radius-md);
  padding: 12px;
  text-align: center;
}

.cockpit-metric-card span {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-subtle);
  display: block;
  margin-bottom: 4px;
}

.cockpit-metric-card strong {
  font-size: 1.18rem;
  color: #FFFFFF;
}

.cockpit-terminal {
  background: #03050A;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: #94A3B8;
  line-height: 1.7;
}

.cockpit-terminal .kw { color: #F43F5E; font-weight: 600; }
.cockpit-terminal .str { color: var(--cyan-bright); }
.cockpit-terminal .num { color: var(--gold-light); }
.cockpit-terminal .fn { color: #10B981; }
.cockpit-terminal .com { color: #64748B; font-style: italic; }

/* ==========================================================================
   SECTION 2: CÁCH THỨC HOẠT ĐỘNG (HOW IT WORKS) - CYBER PIPELINE
   ========================================================================== */
.section-how {
  padding: 100px 0;
  position: relative;
  background: radial-gradient(circle at 50% 50%, rgba(10, 148, 115, 0.08) 0%, transparent 60%);
}

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 60px;
}

.section-subtitle {
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan-bright);
  font-family: var(--font-mono);
  margin-bottom: 12px;
  display: block;
}

.section-title {
  font-size: clamp(2rem, 3.6vw, 2.8rem);
  font-weight: 800;
  color: #FFFFFF;
  margin-bottom: 16px;
}

.section-lead {
  font-size: 1.05rem;
  color: var(--text-muted);
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  position: relative;
}

.step-card {
  background: var(--bg-surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 38px 30px;
  backdrop-filter: blur(16px);
  transition: all 0.35s ease;
  position: relative;
  overflow: hidden;
}

.step-card:hover {
  transform: translateY(-8px);
  border-color: var(--cyan-bright);
  box-shadow: 0 20px 45px rgba(0, 0, 0, 0.7), 0 0 25px rgba(43, 210, 228, 0.2);
}

.step-number {
  position: absolute;
  top: 18px;
  right: 24px;
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 800;
  color: rgba(43, 210, 228, 0.12);
  line-height: 1;
}

.step-icon-wrap {
  width: 64px;
  height: 64px;
  border-radius: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  background: rgba(43, 210, 228, 0.12);
  color: var(--cyan-bright);
  border: 1px solid rgba(43, 210, 228, 0.25);
  box-shadow: 0 0 15px rgba(43, 210, 228, 0.15);
}

.step-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 12px;
}

.step-text {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.65;
}

/* ==========================================================================
   SECTION 3: LỢI ÍCH KÉP (DUAL VALUE MATRIX)
   ========================================================================== */
.section-dual {
  padding: 100px 0;
  position: relative;
}

.dual-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

.dual-card {
  border-radius: var(--radius-xl);
  padding: 44px 38px;
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(20px);
  border: 1px solid var(--border-subtle);
  transition: all 0.35s ease;
}

.dual-card-b2c {
  background: linear-gradient(180deg, rgba(10, 148, 115, 0.12) 0%, rgba(9, 14, 30, 0.85) 100%);
  border-color: rgba(43, 210, 228, 0.28);
}

.dual-card-b2b {
  background: linear-gradient(180deg, rgba(244, 139, 40, 0.1) 0%, rgba(9, 14, 30, 0.85) 100%);
  border-color: rgba(244, 139, 40, 0.28);
}

.dual-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.dual-card-b2c:hover {
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.75), 0 0 30px rgba(43, 210, 228, 0.2);
}

.dual-card-b2b:hover {
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.75), 0 0 30px rgba(244, 139, 40, 0.2);
}

.dual-card-title {
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 24px;
  color: #FFFFFF;
}

.dual-features-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-bottom: 36px;
}

.dual-feature-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  font-size: 0.96rem;
  color: var(--text-main);
  line-height: 1.6;
}

.check-icon {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 2px;
  font-size: 0.85rem;
  font-weight: 800;
}

.check-b2c {
  background: rgba(43, 210, 228, 0.15);
  color: var(--cyan-bright);
  border: 1px solid rgba(43, 210, 228, 0.4);
}

.check-b2b {
  background: rgba(244, 139, 40, 0.15);
  color: var(--gold-light);
  border: 1px solid rgba(244, 139, 40, 0.4);
}

/* ==========================================================================
   SECTION 4: LĨNH VỰC ÁP DỤNG (CATEGORIES)
   ========================================================================== */
.section-categories {
  padding: 100px 0;
  position: relative;
}

.categories-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
}

.category-card {
  background: var(--bg-surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 30px 20px;
  text-align: center;
  transition: all 0.3s ease;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.category-card:hover {
  transform: translateY(-8px);
  border-color: var(--cyan-bright);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.7), 0 0 20px rgba(43, 210, 228, 0.2);
}

.cat-icon-circle {
  width: 68px;
  height: 68px;
  border-radius: 50%;
  background: rgba(43, 210, 228, 0.1);
  color: var(--cyan-bright);
  border: 1px solid rgba(43, 210, 228, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  transition: all 0.3s ease;
}

.category-card:hover .cat-icon-circle {
  background: linear-gradient(135deg, var(--teal-main), var(--cyan-bright));
  color: #FFFFFF;
  transform: scale(1.1);
  box-shadow: 0 0 20px rgba(43, 210, 228, 0.5);
}

.cat-name {
  font-size: 1.05rem;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 10px;
}

.cat-cashback-badge {
  font-size: 0.76rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--gold-light);
  background: rgba(244, 139, 40, 0.15);
  border: 1px solid rgba(244, 139, 40, 0.3);
  padding: 4px 12px;
  border-radius: var(--radius-full);
}

/* ==========================================================================
   SECTION 5: BOTTOM CALL TO ACTION
   ========================================================================== */
.section-bottom-cta {
  padding: 110px 0;
  position: relative;
  overflow: hidden;
  background: linear-gradient(180deg, transparent 0%, #03050A 100%);
  border-top: 1px solid rgba(43, 210, 228, 0.14);
}

.cta-box {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 840px;
  margin: 0 auto;
}

.cta-title {
  font-size: clamp(2.2rem, 4vw, 3.2rem);
  font-weight: 800;
  color: #FFFFFF;
  line-height: 1.2;
  margin-bottom: 20px;
}

.cta-sub {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-bottom: 40px;
  line-height: 1.7;
}

.cta-btn-group {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* ==========================================================================
   Subpage Headers & Modules (B2C, B2B, About, News, etc.)
   ========================================================================== */
.subpage-hero {
  padding: 80px 0 70px;
  position: relative;
  border-bottom: 1px solid rgba(43, 210, 228, 0.12);
  background: radial-gradient(circle at 50% 20%, rgba(43, 210, 228, 0.12) 0%, transparent 60%);
}

.subpage-hero-center {
  text-align: center;
  max-width: 780px;
  margin: 0 auto;
}

/* Alternating Feature Rows */
.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 60px;
  padding: 70px 0;
}

.feature-row.reverse {
  direction: rtl;
}

.feature-row.reverse > * {
  direction: ltr;
}

.feature-visual-box {
  background: var(--bg-surface-card);
  border-radius: var(--radius-xl);
  padding: 40px;
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  backdrop-filter: blur(16px);
}

/* Interactive AI Cashback Calculator Widget */
.calc-card {
  background: var(--bg-surface-card);
  border-radius: var(--radius-xl);
  padding: 44px;
  box-shadow: var(--shadow-lg), 0 0 35px rgba(43, 210, 228, 0.12);
  border: 1px solid rgba(43, 210, 228, 0.35);
  max-width: 760px;
  margin: 40px auto 0;
  backdrop-filter: blur(20px);
}

.calc-slider-wrap {
  margin: 32px 0;
}

.calc-slider {
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: #1E293B;
  outline: none;
  -webkit-appearance: none;
  cursor: pointer;
}

.calc-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--gold-light), var(--orange-main));
  box-shadow: 0 0 15px rgba(244, 139, 40, 0.7);
  cursor: pointer;
}

.calc-result-box {
  background: rgba(10, 148, 115, 0.12);
  border: 1px solid rgba(43, 210, 228, 0.3);
  border-radius: var(--radius-lg);
  padding: 26px;
  text-align: center;
  margin-top: 28px;
}

.calc-result-num {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--cyan-bright);
}

/* Pricing Grid (B2B) */
.pricing-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  max-width: 920px;
  margin: 40px auto 0;
}

.pricing-card {
  background: var(--bg-surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 40px;
  position: relative;
  transition: all 0.3s ease;
  backdrop-filter: blur(16px);
}

.pricing-card.featured {
  border-color: var(--cyan-bright);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.8), 0 0 30px rgba(43, 210, 228, 0.2);
}

/* ==========================================================================
   Modals & Forms in Cyber Dark Style
   ========================================================================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(3, 5, 10, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal-content {
  background: #090E1E;
  border: 1px solid rgba(43, 210, 228, 0.3);
  border-radius: var(--radius-xl);
  max-width: 580px;
  width: 100%;
  padding: 38px;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.9), 0 0 40px rgba(43, 210, 228, 0.2);
  position: relative;
  transform: translateY(20px) scale(0.96);
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  max-height: 90vh;
  overflow-y: auto;
  color: #FFFFFF;
}

.modal-overlay.active .modal-content {
  transform: translateY(0) scale(1);
}

.modal-close-btn {
  position: absolute;
  top: 20px;
  right: 20px;
  background: rgba(255, 255, 255, 0.08);
  border: none;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-muted);
  transition: all 0.2s ease;
}

.modal-close-btn:hover {
  background: rgba(255, 255, 255, 0.15);
  color: #FFFFFF;
}

.form-group {
  margin-bottom: 18px;
}

.form-label {
  display: block;
  font-size: 0.86rem;
  font-weight: 600;
  color: #CBD5E1;
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-md);
  background: rgba(14, 22, 44, 0.7);
  color: #FFFFFF;
  outline: none;
  transition: all 0.2s ease;
}

.form-control:focus {
  border-color: var(--cyan-bright);
  box-shadow: 0 0 0 3px rgba(43, 210, 228, 0.2);
  background: rgba(14, 22, 44, 0.95);
}

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

/* ==========================================================================
   Global Footer (Deep Space Enterprise)
   ========================================================================== */
.site-footer {
  background: #03050A;
  color: var(--text-muted);
  padding: 80px 0 36px;
  border-top: 1px solid rgba(43, 210, 228, 0.15);
  position: relative;
  z-index: 2;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.35fr 0.9fr 0.9fr 1.1fr;
  gap: 48px;
  margin-bottom: 60px;
}

.footer-col h5 {
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: #FFFFFF;
  margin-bottom: 22px;
  position: relative;
  font-family: var(--font-mono);
}

.footer-col h5::after {
  content: "";
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 28px;
  height: 2px;
  background: var(--cyan-bright);
  box-shadow: 0 0 8px var(--cyan-bright);
  border-radius: 2px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.92rem;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--cyan-bright);
  padding-left: 4px;
}

.footer-company-card {
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--text-muted);
  margin-top: 16px;
}

/* Enterprise Tax & Legal Card (Synced from tas-site-v2) */
.footer-tax-card {
  background: rgba(43, 210, 228, 0.04);
  border: 1px solid rgba(43, 210, 228, 0.18);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--text-muted);
  margin-top: 16px;
  backdrop-filter: blur(10px);
}

.footer-tax-card p {
  margin: 0 0 6px 0;
}

.footer-tax-card p:last-child {
  margin-bottom: 0;
}

.footer-tax-card strong {
  color: #FFFFFF;
}

.tax-code-glow {
  color: var(--cyan-bright);
  font-family: var(--font-mono);
  font-weight: 700;
  letter-spacing: 0.05em;
  background: rgba(43, 210, 228, 0.1);
  padding: 2px 7px;
  border-radius: 4px;
  border: 1px solid rgba(43, 210, 228, 0.35);
  display: inline-block;
  margin-left: 4px;
}

.footer-contact-item {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 10px;
  color: #FFFFFF;
  font-weight: 600;
}

.footer-qr-badge-box {
  display: flex;
  gap: 16px;
  align-items: center;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  padding: 14px;
  border-radius: 16px;
  margin-bottom: 16px;
}

.footer-qr-img {
  width: 76px;
  height: 76px;
  background: #FFFFFF;
  border-radius: 8px;
  padding: 4px;
}

.app-store-badges {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.store-badge-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 10px;
  padding: 7px 12px;
  color: #FFFFFF;
  font-size: 0.8rem;
  transition: all 0.2s ease;
}

.store-badge-btn:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: var(--cyan-bright);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 26px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.86rem;
  color: var(--text-muted);
}

.footer-legal {
  display: flex;
  gap: 18px;
}

.footer-legal a:hover {
  color: var(--cyan-bright);
}

/* Toast */
.toast-notice {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: #090E1E;
  color: #FFFFFF;
  padding: 16px 24px;
  border-radius: var(--radius-md);
  box-shadow: 0 10px 35px rgba(0, 0, 0, 0.8);
  border-left: 4px solid var(--cyan-bright);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  border-right: 1px solid rgba(255, 255, 255, 0.1);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  z-index: 3000;
  transform: translateY(100px);
  opacity: 0;
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.92rem;
}

.toast-notice.show {
  transform: translateY(0);
  opacity: 1;
}

/* ==========================================================================
   Responsive Breakpoints & Laptop Display Optimization
   ========================================================================== */

/* Laptop Standard (1366px - 1440px) */
@media (max-width: 1366px) {
  .header-container {
    padding: 0 16px;
    gap: 12px;
  }
  .brand-wrapper {
    gap: 10px;
  }
  .brand-logo-img {
    height: 38px;
  }
  .brand-info h1 {
    font-size: 1.08rem;
  }
  .desktop-nav {
    gap: 4px;
  }
  .desktop-nav .nav-link {
    padding: 7px 12px;
    font-size: 0.9rem;
  }
  .header-actions {
    gap: 8px;
  }
  .btn-sm {
    padding: 7px 14px;
    font-size: 0.83rem;
  }
}

/* Laptop Compact / 1280px / 1366px @ 125% DPI Scale */
@media (max-width: 1240px) {
  .desktop-nav {
    gap: 3px;
  }
  .desktop-nav .nav-link {
    padding: 6px 10px;
    font-size: 0.88rem;
  }
  .ai-live-beacon .beacon-label {
    display: none;
  }
  .ai-live-beacon {
    padding: 6px 8px;
  }
}

/* Tablet Landscape / Small Laptop (< 1080px) */
@media (max-width: 1080px) {
  .desktop-nav {
    display: none !important;
  }
  .header-actions .btn-action-merchant {
    display: none !important;
  }
  .mobile-toggle-btn {
    display: flex !important;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    color: #FFFFFF;
    padding: 8px;
    cursor: pointer;
  }
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 48px;
  }
  .hero-desc {
    margin-left: auto;
    margin-right: auto;
  }
  .hero-actions {
    justify-content: center;
  }
  .categories-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }
}

/* Mobile & Small Tablets (< 768px) */
@media (max-width: 768px) {
  .header-actions .btn-action-download {
    display: none !important;
  }
  .steps-grid {
    grid-template-columns: 1fr;
  }
  .dual-grid {
    grid-template-columns: 1fr;
  }
  .categories-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .feature-row {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .pricing-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 14px;
    text-align: center;
  }
  .form-row {
    grid-template-columns: 1fr;
  }
  .hero-trust-indicators {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .brand-tagline {
    display: none;
  }
  .categories-grid {
    grid-template-columns: 1fr;
  }
}