/* ===================================================================
   VIBE CODING — HIGH-END EDITORIAL / BRUTALIST DESIGN SYSTEM
   Fonts: Big Shoulders Display (Headlines/CTA) | Inter (Body/UI) | Cormorant Garamond (Quotes)
   Colors: Obsidian #0B0908 | Warm Paper #F4EDE3 | Terracotta #B8552F | Slate #2C4A5C
   =================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Big+Shoulders+Display:wght@400;500;600;700;800;900&family=Cormorant+Garamond:ital,wght@0,500;0,600;0,700;1,400;1,600&family=Inter:wght@300;400;500;600;700;800&display=swap');

:root {
  --font-display: 'Big Shoulders Display', -apple-system, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-serif: 'Cormorant Garamond', Georgia, serif;

  /* Colors */
  --bg-dark: #0B0908;
  --bg-dark-surface: #14100D;
  --bg-dark-card: #1A1410;
  --bg-dark-border: rgba(244, 237, 227, 0.12);
  
  --bg-paper: #F4EDE3;
  --bg-paper-alt: #EBE2D5;
  --bg-paper-card: #FFFFFF;
  --border-paper: #E2D7C8;
  --border-paper-dark: #CFC1AF;

  --color-terracotta: #B8552F;
  --color-terracotta-hover: #9E4321;
  --color-terracotta-light: #F7EDE8;
  --color-terracotta-tint: rgba(184, 85, 47, 0.08);

  --color-slate: #2C4A5C;
  --color-slate-light: #3D647C;
  --color-slate-tint: rgba(44, 74, 92, 0.08);

  --text-dark-primary: #14100D;
  --text-dark-secondary: #5A524A;
  --text-dark-muted: #847B71;

  --text-light-primary: #F4EDE3;
  --text-light-secondary: #C8BFB5;
  --text-light-muted: #8C8277;

  --shadow-brutalist: 4px 4px 0px #0B0908;
  --shadow-paper: 0 10px 30px -10px rgba(20, 16, 13, 0.08), 0 2px 6px rgba(20, 16, 13, 0.04);
  --shadow-paper-hover: 0 16px 40px -10px rgba(20, 16, 13, 0.14), 0 4px 12px rgba(20, 16, 13, 0.06);

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;
  --max-width: 1160px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--text-dark-primary);
  background-color: var(--bg-dark);
  overflow-x: hidden;
  position: relative;
  -webkit-font-smoothing: antialiased;
}

/* Subtle Grain Overlay */
.grain-overlay {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 999;
  opacity: 0.035;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
}

/* Container */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

.container-narrow {
  max-width: 840px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* Top Nav / Brand Bar */
.top-bar {
  background: var(--bg-dark);
  border-bottom: 1px solid var(--bg-dark-border);
  padding: 16px 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
  background-color: rgba(11, 9, 8, 0.92);
}

.top-bar-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}

.top-bar-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-logo-link {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.top-bar-logo {
  height: 36px;
  width: auto;
  max-width: 155px;
  object-fit: contain;
  display: block;
}

.brand-divider {
  color: rgba(244, 237, 227, 0.25);
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
}

.brand-course-tag {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--text-light-secondary);
  text-transform: uppercase;
}

.brand-author {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-terracotta);
}


.top-bar-cta {
  display: inline-flex;
  align-items: center;
  padding: 8px 18px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.1rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  background: var(--color-terracotta);
  color: #FFF;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: all 0.2s ease;
}

.top-bar-cta:hover {
  background: var(--color-terracotta-hover);
  transform: translateY(-1px);
}

/* Sections Global */
.section {
  padding: 96px 0;
  position: relative;
}

.section.theme-dark {
  background-color: var(--bg-dark);
  color: var(--text-light-primary);
}

.section.theme-dark-alt {
  background-color: var(--bg-dark-surface);
  color: var(--text-light-primary);
  border-top: 1px solid var(--bg-dark-border);
  border-bottom: 1px solid var(--bg-dark-border);
}

.section.theme-paper {
  background-color: var(--bg-paper);
  color: var(--text-dark-primary);
}

.section.theme-paper-alt {
  background-color: var(--bg-paper-alt);
  color: var(--text-dark-primary);
  border-top: 1px solid var(--border-paper);
  border-bottom: 1px solid var(--border-paper);
}

/* Eyebrows & Numbers */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.theme-dark .eyebrow {
  color: var(--color-terracotta);
}

.theme-paper .eyebrow {
  color: var(--color-terracotta);
}

.section-number {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  padding: 4px 10px;
  background: rgba(184, 85, 47, 0.14);
  color: var(--color-terracotta);
  border-radius: var(--radius-sm);
  display: inline-block;
  margin-bottom: 20px;
  border: 1px solid rgba(184, 85, 47, 0.3);
}

.theme-paper .section-number {
  background: #FFF;
  border-color: var(--border-paper-dark);
  color: var(--text-dark-primary);
}

/* Headings */
.headline-huge {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 6.2vw, 5.5rem);
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: 0;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.headline-large {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 4.5vw, 3.8rem);
  font-weight: 900;
  line-height: 1.24;
  letter-spacing: 0.005em;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.headline-medium {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3.2vw, 2.5rem);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: 0.01em;
  text-transform: uppercase;
  margin-bottom: 18px;
}

.headline-card {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  margin-bottom: 12px;
}

/* Editorial Quotes */
.editorial-quote {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: clamp(1.2rem, 2.4vw, 1.65rem);
  line-height: 1.45;
  padding: 24px 32px;
  border-left: 3px solid var(--color-terracotta);
  margin: 36px 0;
  background: rgba(184, 85, 47, 0.05);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.theme-dark .editorial-quote {
  color: #FAF5EE;
  background: rgba(255, 255, 255, 0.03);
}

.theme-paper .editorial-quote {
  color: #241D17;
  background: #FFF;
  border: 1px solid var(--border-paper);
  border-left: 3px solid var(--color-terracotta);
  box-shadow: var(--shadow-paper);
}

/* Highlight Poster Boxes */
.poster-highlight {
  background: var(--color-terracotta);
  color: #FFF;
  padding: 6px 14px;
  display: inline-block;
  font-weight: 800;
  letter-spacing: 0.02em;
}

/* Primary CTA Buttons */
.btn-cta {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px 48px;
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 2.6vw, 1.9rem);
  font-weight: 900;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: #FFF;
  background-color: var(--color-terracotta);
  border: 2px solid var(--color-terracotta-dark);
  border-radius: var(--radius-sm);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 0 8px 24px rgba(184, 85, 47, 0.35);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.btn-cta:hover {
  background-color: var(--color-terracotta-hover);
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(184, 85, 47, 0.45);
}

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

.btn-cta-sub {
  font-family: var(--font-body);
  font-size: 0.92rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  text-transform: none;
  opacity: 0.9;
  margin-top: 4px;
}

.btn-cta-full {
  width: 100%;
}

/* ===================================================================
   SPECIFIC SECTION STYLES
   =================================================================== */

/* SECTION 1: HERO */
.hero-wrap {
  padding: 44px 0 88px;
  position: relative;
  overflow: hidden;
}

.hero-wrap::before {
  content: "";
  position: absolute;
  top: -120px;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 480px;
  background: radial-gradient(circle, rgba(184, 85, 47, 0.08) 0%, rgba(11, 9, 8, 0) 70%);
  pointer-events: none;
  z-index: 0;
}

.hero-wrap > .container {
  position: relative;
  z-index: 1;
}

/* Centered Hero Header */
.hero-header-center {
  text-align: center;
  max-width: 1040px;
  margin: 0 auto 48px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* Hero Brand Badge with Logo */
.hero-brand-badge {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  background: rgba(244, 237, 227, 0.035);
  border: 1px solid rgba(244, 237, 227, 0.12);
  padding: 8px 18px 8px 14px;
  border-radius: 9999px;
  margin-bottom: 22px;
  backdrop-filter: blur(8px);
}

.hero-brand-logo {
  height: 26px;
  width: auto;
  max-width: 120px;
  object-fit: contain;
  display: block;
}

.hero-badge-tag {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-terracotta);
  border-left: 1px solid rgba(244, 237, 227, 0.15);
  padding-left: 12px;
}

.hero-eyebrow-wrap {
  margin-bottom: 18px;
  text-align: center;
  width: 100%;
}

.hero-eyebrow {
  display: inline-block;
  font-family: var(--font-display);
  font-size: clamp(0.95rem, 1.5vw, 1.15rem);
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-terracotta);
  max-width: 860px;
  line-height: 1.55;
  margin-bottom: 0;
  text-align: center;
}

.hero-headline {
  font-size: clamp(2.3rem, 4.4vw, 4rem);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: 0.01em;
  color: var(--text-light-primary);
  margin: 0 auto 22px;
  max-width: 1020px;
  text-align: center;
  text-wrap: balance;
}

.hero-headline-br {
  display: block;
}

.hero-subline {
  display: inline-block;
  color: var(--text-light-primary);
  letter-spacing: 0.02em;
}

.hero-hl {
  color: #B75632;
  text-decoration: none;
  font-weight: inherit;
}

.highlight-underline {
  color: #B75632;
  text-decoration: none;
}

.hero-subhead {
  font-size: clamp(1.05rem, 1.5vw, 1.25rem);
  color: var(--text-light-secondary);
  line-height: 1.75;
  max-width: 840px;
  margin: 0 auto;
  text-align: center;
}

/* 2-Column Hero Grid */
.hero-grid {
  display: grid;
  grid-template-columns: 1.12fr 0.88fr;
  gap: 38px;
  align-items: start;
}

.hero-col-main {
  display: flex;
  flex-direction: column;
}

.hero-bullets {
  list-style: none;
  margin: 0 0 32px 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.hero-bullet-item {
  background: rgba(244, 237, 227, 0.03);
  border: 1px solid rgba(244, 237, 227, 0.09);
  padding: 16px 22px;
  border-radius: var(--radius-md);
  font-size: 1.05rem;
  line-height: 1.6;
  color: var(--text-light-primary);
  display: flex;
  align-items: flex-start;
  gap: 14px;
  transition: transform 0.2s ease, border-color 0.2s ease, background-color 0.2s ease;
}

.hero-bullet-item:hover {
  transform: translateX(4px);
  border-color: rgba(184, 85, 47, 0.4);
  background: rgba(244, 237, 227, 0.045);
}

.hero-bullet-icon {
  color: var(--color-terracotta);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.3rem;
  line-height: 1;
  margin-top: 2px;
  flex-shrink: 0;
}

.hero-cta-box {
  margin-top: 4px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 14px;
}

.hero-btn-cta {
  width: 100%;
  max-width: 480px;
}

.hero-guarantee-note {
  font-size: 0.88rem;
  color: var(--text-light-muted);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 2px;
}

.hero-guarantee-note .sep {
  color: rgba(244, 237, 227, 0.3);
}

/* Side Column: Frame & Quote */
.hero-col-side {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.hero-card-frame {
  background: #14110F;
  border: 1px solid rgba(244, 237, 227, 0.14);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: 0 20px 48px -10px rgba(0, 0, 0, 0.6);
}

.hero-card-header {
  background: rgba(244, 237, 227, 0.04);
  border-bottom: 1px solid rgba(244, 237, 227, 0.08);
  padding: 10px 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.window-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}

.window-dot.red { background: #FF5F56; }
.window-dot.yellow { background: #FFBD2E; }
.window-dot.green { background: #27C93F; }

.window-caption {
  font-family: var(--font-display);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  color: var(--text-light-muted);
  margin-left: 6px;
  text-transform: uppercase;
}

.hero-card-img-wrap {
  width: 100%;
  background: #0B0908;
  overflow: hidden;
}

.hero-card-img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.hero-card-frame:hover .hero-card-img {
  transform: scale(1.02);
}

.hero-card-footer {
  padding: 12px 16px;
  background: rgba(244, 237, 227, 0.02);
  border-top: 1px solid rgba(244, 237, 227, 0.06);
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.hero-card-pill {
  font-family: var(--font-display);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  padding: 3px 8px;
  background: rgba(244, 237, 227, 0.06);
  color: var(--text-light-secondary);
  border-radius: 4px;
  text-transform: uppercase;
}

.hero-card-pill.highlight {
  background: rgba(184, 85, 47, 0.2);
  color: var(--color-terracotta);
  border: 1px solid rgba(184, 85, 47, 0.4);
}

.hero-editorial-quote {
  margin: 0;
  padding: 22px 24px;
  font-size: 1.12rem;
  line-height: 1.55;
  border-left: 3px solid var(--color-terracotta);
  background: rgba(244, 237, 227, 0.035);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  border-top: 1px solid rgba(244, 237, 227, 0.06);
  border-right: 1px solid rgba(244, 237, 227, 0.06);
  border-bottom: 1px solid rgba(244, 237, 227, 0.06);
}

.hero-quote-signature {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 14px;
}

.hero-quote-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--color-terracotta);
}

.hero-quote-signature strong {
  display: block;
  font-family: var(--font-display);
  font-size: 0.95rem;
  color: var(--text-light-primary);
  letter-spacing: 0.04em;
}

.hero-quote-signature small {
  display: block;
  font-size: 0.82rem;
  color: var(--text-light-muted);
}


/* SECTION 2: XEM TRƯỚC SẢN PHẨM */
.preview-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin: 44px 0 36px;
}

.preview-card {
  background: var(--bg-paper-card);
  border: 1.5px solid var(--border-paper-dark);
  border-radius: var(--radius-md);
  padding: 0;
  box-shadow: var(--shadow-paper);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s ease, border-color 0.25s ease;
  position: relative;
  cursor: pointer;
}

.preview-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 42px -10px rgba(20, 16, 13, 0.16), 0 6px 16px rgba(20, 16, 13, 0.06);
  border-color: var(--color-terracotta);
}

.preview-media-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #EAE2D5;
  overflow: hidden;
  border-bottom: 1.5px solid var(--border-paper);
}

.preview-banner-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

.preview-card:hover .preview-banner-img {
  transform: scale(1.03);
}

.preview-zoom-btn {
  position: absolute;
  bottom: 12px;
  right: 12px;
  background: rgba(11, 9, 8, 0.72);
  backdrop-filter: blur(6px);
  color: #FFF;
  width: 34px;
  height: 34px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 0.25s ease, transform 0.25s ease, background-color 0.2s ease;
  border: 1px solid rgba(244, 237, 227, 0.2);
  pointer-events: none;
}

.preview-card:hover .preview-zoom-btn {
  opacity: 1;
  transform: translateY(0);
}

.preview-card-body {
  padding: 24px 26px 26px;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
  justify-content: space-between;
}

.preview-header-row {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.preview-card .headline-card {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: 0.02em;
  color: var(--text-dark-primary);
  margin-bottom: 0;
}

.preview-desc {
  color: var(--text-dark-secondary);
  font-size: 1rem;
  line-height: 1.65;
  margin-top: 6px;
}

.preview-badge {
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-slate);
  background: rgba(44, 74, 92, 0.08);
  border: 1px solid rgba(44, 74, 92, 0.25);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  display: inline-block;
  white-space: nowrap;
  align-self: flex-start;
}

/* Lightbox Modal */
.lightbox-modal {
  position: fixed;
  inset: 0;
  background: rgba(11, 9, 8, 0.88);
  backdrop-filter: blur(8px);
  z-index: 9999;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
  cursor: zoom-out;
  opacity: 0;
  transition: opacity 0.25s ease;
}

.lightbox-modal.active {
  display: flex;
  opacity: 1;
}

.lightbox-content {
  position: relative;
  max-width: 1200px;
  width: 100%;
  cursor: default;
  display: flex;
  flex-direction: column;
  align-items: center;
  animation: lightboxPop 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes lightboxPop {
  from { transform: scale(0.96); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.lightbox-img {
  width: 100%;
  height: auto;
  max-height: 82vh;
  object-fit: contain;
  border-radius: var(--radius-sm);
  border: 1.5px solid rgba(244, 237, 227, 0.2);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.65);
  background: #14100D;
}

.lightbox-caption {
  color: var(--text-light-primary);
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  margin-top: 14px;
  text-align: center;
}

.lightbox-close {
  position: absolute;
  top: -42px;
  right: 0;
  background: transparent;
  border: none;
  color: #FFF;
  font-size: 2.2rem;
  cursor: pointer;
  line-height: 1;
  padding: 4px;
  opacity: 0.8;
  transition: opacity 0.2s;
}

.lightbox-close:hover {
  opacity: 1;
  color: var(--color-terracotta);
}

@media (max-width: 768px) {
  .preview-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .preview-card-body {
    padding: 18px 20px 20px;
  }
  .preview-card .headline-card {
    font-size: 1.35rem;
  }
  .preview-zoom-btn {
    opacity: 0.9;
    transform: translateY(0);
  }
}

.preview-outro {
  background: #FFF;
  border: 1.5px dashed var(--border-paper-dark);
  border-radius: var(--radius-md);
  padding: 28px 32px;
  margin-top: 24px;
  font-size: 1.15rem;
  line-height: 1.8;
}

/* SECTION 3: VẤN ĐỀ THẬT SỰ */
.problem-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  margin-top: 40px;
}

.problem-narrative {
  background: var(--bg-dark-card);
  border: 1px solid var(--bg-dark-border);
  padding: 36px 32px;
  border-radius: var(--radius-md);
  font-size: 1.05rem;
  line-height: 1.85;
}

.problem-narrative p {
  margin-bottom: 12px;
}

.problem-narrative p:last-child {
  margin-bottom: 0;
}

.problem-alert-box {
  background: rgba(184, 85, 47, 0.08);
  border: 1.5px solid var(--color-terracotta);
  padding: 36px 32px;
  border-radius: var(--radius-md);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.problem-list {
  list-style: none;
  margin: 20px 0;
}

.problem-list li {
  padding: 10px 0 10px 24px;
  position: relative;
  font-size: 1.02rem;
  color: var(--text-light-primary);
  border-bottom: 1px solid rgba(244, 237, 227, 0.08);
}

.problem-list li:last-child {
  border-bottom: none;
}

.problem-list li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--color-terracotta);
  font-weight: bold;
}

/* SECTION 4: VÒNG LẶP VIBE CODING */
.loop-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
  margin: 44px 0 36px;
}

.loop-step-card {
  background: var(--bg-paper-card);
  border: 1.5px solid var(--border-paper-dark);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  box-shadow: var(--shadow-paper);
  position: relative;
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s ease, border-color 0.25s ease;
}

.loop-step-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-terracotta);
  box-shadow: 0 16px 36px -6px rgba(20, 16, 13, 0.12);
}

.loop-step-num {
  font-family: var(--font-display);
  font-size: 3rem;
  font-weight: 900;
  line-height: 1;
  color: var(--color-terracotta);
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.loop-step-card .headline-card {
  font-family: var(--font-display);
  font-size: 1.55rem;
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: 0.02em;
  margin-bottom: 14px;
}

.loop-difference-box {
  background: #FFF;
  border: 2px solid var(--text-dark-primary);
  border-radius: var(--radius-md);
  padding: 40px;
  margin-top: 32px;
  box-shadow: 6px 6px 0px var(--text-dark-primary);
}

/* SECTION 5: SO SÁNH DEMO VS SẢN PHẨM THẬT */
.compare-table-wrap {
  margin: 40px 0;
  overflow-x: auto;
  border: 1.5px solid var(--border-paper-dark);
  border-radius: var(--radius-md);
  background: #FFF;
  box-shadow: var(--shadow-paper);
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.compare-table th, .compare-table td {
  padding: 16px 20px;
  font-size: 1rem;
  border-bottom: 1px solid var(--border-paper);
}

.compare-table th {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: var(--bg-paper-alt);
  color: var(--text-dark-primary);
}

.compare-table th:nth-child(2) {
  color: var(--text-dark-muted);
}

.compare-table th:nth-child(3) {
  color: var(--color-terracotta);
}

.compare-table tr:last-child td {
  border-bottom: none;
}

.compare-table td:nth-child(1) {
  font-weight: 600;
  color: var(--text-dark-primary);
  width: 25%;
}

.compare-table td:nth-child(2) {
  color: var(--text-dark-secondary);
  width: 37.5%;
}

.compare-table td:nth-child(3) {
  font-weight: 600;
  color: var(--color-terracotta);
  width: 37.5%;
  background: rgba(184, 85, 47, 0.03);
}

.compare-summary {
  background: #FFF;
  border-left: 4px solid var(--color-terracotta);
  padding: 24px 28px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin-top: 24px;
  font-size: 1.1rem;
  line-height: 1.8;
  box-shadow: var(--shadow-paper);
}

/* SECTION 6: BẮT ĐẦU TỪ NHỮNG GÌ BẠN ĐANG CÓ */
.prereq-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  margin: 40px 0;
}

.prereq-card {
  padding: 36px 32px;
  border-radius: var(--radius-md);
}

.prereq-card.need {
  background: rgba(44, 74, 92, 0.15);
  border: 1.5px solid var(--color-slate-light);
}

.prereq-card.not-need {
  background: var(--bg-dark-card);
  border: 1px solid var(--bg-dark-border);
}

.prereq-list {
  list-style: none;
  margin-top: 20px;
}

.prereq-list li {
  padding: 10px 0 10px 28px;
  position: relative;
  font-size: 1.05rem;
  color: var(--text-light-primary);
  border-bottom: 1px solid rgba(244, 237, 227, 0.08);
}

.prereq-list li:last-child {
  border-bottom: none;
}

.prereq-card.need .prereq-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: #48BB78;
  font-weight: bold;
}

.prereq-card.not-need .prereq-list li::before {
  content: "✕";
  position: absolute;
  left: 0;
  color: var(--color-terracotta);
  font-weight: bold;
}

/* SECTION 7: NGƯỜI HƯỚNG DẪN */
.instructor-wrap {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 48px;
  align-items: start;
  margin-top: 40px;
}

.instructor-photo-card {
  width: 100%;
  max-width: 360px;
  background: var(--bg-paper-card);
  border: 2px solid var(--text-dark-primary);
  border-radius: var(--radius-md);
  padding: 18px;
  box-shadow: 6px 6px 0px var(--text-dark-primary);
  text-align: center;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  align-self: start;
}

.instructor-photo-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 8px 8px 0px var(--color-terracotta);
}

.instructor-img-box {
  width: 100%;
  aspect-ratio: 1 / 1;
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-paper-dark);
  box-shadow: 0 4px 14px rgba(20, 16, 13, 0.06);
  background: #EAE3D9;
}

.instructor-img {
  width: 100%;
  height: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  object-position: center center;
  display: block;
}

.instructor-caption {
  font-family: var(--font-display);
  font-size: 1.45rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 16px;
  color: var(--text-dark-primary);
}

.instructor-bio {
  font-size: 1.08rem;
  line-height: 1.85;
  color: var(--text-dark-primary);
}

.instructor-bio p {
  margin-bottom: 16px;
}

/* SECTION 8: TỪ Ý TƯỞNG ĐẾN APP CHẠY THẬT */
.milestone-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
  margin: 40px 0;
}

.milestone-card {
  background: var(--bg-dark-card);
  border: 1px solid var(--bg-dark-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: border-color 0.2s ease;
}

.milestone-card:hover {
  border-color: var(--color-terracotta);
}

.milestone-header {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-terracotta);
  margin-bottom: 12px;
}

.milestone-output {
  margin-top: 20px;
  padding: 10px 14px;
  background: rgba(244, 237, 227, 0.05);
  border-left: 2px solid var(--color-terracotta);
  font-size: 0.95rem;
  color: #FFF;
  font-weight: 600;
}

/* SECTION 9: DỰ ÁN THỰC TẾ */
.project-focus-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  margin-top: 40px;
}

.project-focus-box {
  background: var(--bg-paper-card);
  border: 1px solid var(--border-paper);
  border-radius: var(--radius-md);
  padding: 36px 32px;
  box-shadow: var(--shadow-paper);
}

.why-project-list {
  list-style: none;
  margin: 20px 0;
}

.why-project-list li {
  padding: 10px 0;
  font-size: 1.05rem;
  line-height: 1.7;
}

/* SECTION 10: TRỞ NGẠI */
.obstacle-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin: 40px 0;
}

.obstacle-card {
  background: var(--bg-dark-card);
  border: 1px solid var(--bg-dark-border);
  border-radius: var(--radius-md);
  padding: 32px 26px;
  transition: transform 0.2s ease;
}

.obstacle-card:hover {
  transform: translateY(-2px);
  border-color: var(--color-terracotta);
}

.obstacle-title {
  font-family: var(--font-display);
  font-size: 1.45rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--color-terracotta);
  margin-bottom: 14px;
}

/* SECTION 11: BẠN NHẬN ĐƯỢC GÌ */
.deliverables-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
  margin: 40px 0;
}

.deliverable-card {
  background: var(--bg-paper-card);
  border: 1px solid var(--border-paper);
  border-radius: var(--radius-md);
  padding: 24px 22px;
  box-shadow: var(--shadow-paper);
}

.deliverable-num {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--color-terracotta);
  margin-bottom: 6px;
}

.deliverables-highlight {
  background: #FFF;
  border: 2px solid var(--text-dark-primary);
  border-radius: var(--radius-md);
  padding: 32px;
  margin-top: 28px;
  box-shadow: 4px 4px 0px var(--text-dark-primary);
}

/* SECTION 12: CHI PHÍ CẦN CHUẨN BỊ */
.pricing-editorial-box {
  background: var(--bg-dark-card);
  border: 2px solid var(--color-terracotta);
  border-radius: var(--radius-md);
  padding: 48px 40px;
  max-width: 860px;
  margin: 40px auto 0;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
  text-align: center;
}

.price-display {
  font-family: var(--font-display);
  font-size: clamp(3.5rem, 8vw, 6rem);
  font-weight: 900;
  line-height: 0.95;
  color: var(--color-terracotta);
  margin: 16px 0 8px;
}

.price-sub {
  font-size: 1.15rem;
  color: var(--text-light-secondary);
  margin-bottom: 28px;
}

.pricing-notes {
  text-align: left;
  margin: 32px 0;
  padding: 28px 26px;
  background: rgba(244, 237, 227, 0.035);
  border: 1px solid rgba(244, 237, 227, 0.08);
  border-radius: var(--radius-sm);
  font-size: 1rem;
  color: var(--text-light-secondary);
  line-height: 1.8;
}

.pricing-pitch-lead {
  font-size: 1.14rem;
  line-height: 1.75;
  color: #FFF;
  margin-bottom: 14px;
}

.pricing-pitch-lead strong {
  color: var(--color-terracotta);
}

.pricing-pitch strong {
  color: #FFF;
}

.pricing-pillars {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: rgba(184, 85, 47, 0.12);
  border: 1px solid rgba(184, 85, 47, 0.35);
  border-radius: var(--radius-sm);
  padding: 14px 20px;
  margin: 24px 0;
  font-family: var(--font-display);
  font-size: 1.18rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-light-primary);
}

.pricing-pillars .pillar-sep {
  color: var(--color-terracotta);
  font-weight: 900;
}

.pricing-pillars .pillar-item.highlight {
  color: var(--color-terracotta);
}

.pricing-transparency {
  border-top: 1px solid rgba(244, 237, 227, 0.1);
  padding-top: 22px;
  margin-top: 20px;
}

.pricing-transparency-list {
  list-style: none;
  padding: 0;
  margin: 0 0 18px 0;
}

.pricing-transparency-list li {
  padding: 6px 0 6px 20px;
  position: relative;
  font-size: 0.96rem;
  line-height: 1.65;
  color: var(--text-light-secondary);
}

.pricing-transparency-list li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--color-terracotta);
  font-weight: bold;
}

.pricing-honest-note {
  background: rgba(244, 237, 227, 0.035);
  border-left: 3px solid var(--color-terracotta);
  padding: 14px 18px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.94rem;
  line-height: 1.65;
  color: var(--text-light-secondary);
}

.pricing-honest-note strong {
  color: #FFF;
}

/* SECTION 13: PHÙ HỢP VỚI AI */
.audience-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  margin: 40px 0;
}

.audience-card {
  background: var(--bg-paper-card);
  border: 1.5px solid var(--border-paper);
  border-radius: var(--radius-md);
  padding: 36px 32px;
  box-shadow: var(--shadow-paper);
}

.audience-card.positive {
  border-top: 5px solid #2F855A;
}

.audience-card.negative {
  border-top: 5px solid var(--color-terracotta);
}

.audience-list {
  list-style: none;
  margin-top: 20px;
}

.audience-list li {
  padding: 10px 0 10px 24px;
  position: relative;
  font-size: 1.02rem;
  border-bottom: 1px solid var(--border-paper);
}

.audience-list li:last-child {
  border-bottom: none;
}

.audience-card.positive .audience-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: #2F855A;
  font-weight: bold;
}

.audience-card.negative .audience-list li::before {
  content: "✕";
  position: absolute;
  left: 0;
  color: var(--color-terracotta);
  font-weight: bold;
}

/* SECTION 14: FAQ ACCORDION */
.faq-wrap {
  max-width: 860px;
  margin: 40px auto 0;
}

.faq-item {
  background: var(--bg-dark-card);
  border: 1px solid var(--bg-dark-border);
  border-radius: var(--radius-md);
  margin-bottom: 14px;
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item.active {
  border-color: var(--color-terracotta);
}

.faq-header {
  padding: 22px 26px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-question {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--text-light-primary);
  line-height: 1.3;
}

.faq-icon {
  font-size: 1.5rem;
  font-weight: 300;
  color: var(--color-terracotta);
  transition: transform 0.25s ease;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
}

.faq-body {
  padding: 0 26px 24px;
  font-size: 1.02rem;
  line-height: 1.8;
  color: var(--text-light-secondary);
  display: none;
}

.faq-item.active .faq-body {
  display: block;
}

/* SECTION 15: CTA CUỐI */
.final-cta-wrap {
  background: var(--bg-dark-surface);
  border: 2px solid var(--bg-dark-border);
  border-radius: var(--radius-lg);
  padding: 64px 48px;
  text-align: center;
  max-width: 900px;
  margin: 0 auto;
}

.final-cta-checklist {
  text-align: left;
  max-width: 440px;
  margin: 32px auto;
  list-style: none;
}

.final-cta-checklist li {
  padding: 8px 0 8px 28px;
  position: relative;
  font-size: 1.15rem;
  color: var(--text-light-primary);
  font-weight: 600;
}

.final-cta-checklist li::before {
  content: "→";
  position: absolute;
  left: 0;
  color: var(--color-terracotta);
}

/* SECTION 16: FORM ĐĂNG KÝ */
.checkout-section-wrap {
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 40px;
  max-width: 1040px;
  margin: 40px auto 0;
  align-items: start;
}

.order-summary-card {
  background: var(--bg-dark-card);
  border: 2px solid var(--text-dark-primary);
  border-radius: var(--radius-md);
  padding: 36px 32px;
  box-shadow: 6px 6px 0px var(--text-dark-primary);
  color: var(--text-light-primary);
}

.order-form-card {
  background: #FFF;
  border: 2px solid var(--text-dark-primary);
  border-radius: var(--radius-md);
  padding: 36px 32px;
  box-shadow: 6px 6px 0px var(--text-dark-primary);
}

.form-flow-badge {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-terracotta);
  background: var(--color-terracotta-tint);
  border: 1px solid rgba(184, 85, 47, 0.2);
  padding: 4px 12px;
  border-radius: var(--radius-sm);
  display: inline-block;
  margin-bottom: 20px;
}

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

.form-label {
  display: block;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-dark-primary);
  margin-bottom: 8px;
}

.form-input {
  width: 100%;
  padding: 14px 16px;
  font-family: var(--font-body);
  font-size: 1rem;
  border: 1.5px solid var(--border-paper-dark);
  border-radius: var(--radius-sm);
  background: #FFF;
  color: var(--text-dark-primary);
  outline: none;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-input:focus {
  border-color: var(--color-terracotta);
  box-shadow: 0 0 0 3px rgba(184, 85, 47, 0.15);
}

.form-help {
  font-size: 0.84rem;
  color: var(--text-dark-muted);
  margin-top: 6px;
  line-height: 1.5;
}

/* Password Field & Toggle */
.password-input-wrap {
  position: relative;
  width: 100%;
}

.password-input-wrap .form-input {
  padding-right: 48px;
}

.password-toggle-btn {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  background: transparent;
  border: none;
  cursor: pointer;
  color: var(--text-dark-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4px;
  border-radius: var(--radius-sm);
  transition: color 0.15s ease;
}

.password-toggle-btn:hover {
  color: var(--color-terracotta);
}

.password-reminder-box {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  background: rgba(184, 85, 47, 0.08);
  border: 1px solid rgba(184, 85, 47, 0.28);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  margin-top: 8px;
  font-size: 0.88rem;
  line-height: 1.5;
  color: #8C3B1E;
}

.password-reminder-icon {
  font-size: 1.05rem;
  line-height: 1.2;
  flex-shrink: 0;
}

/* Compare table mobile hint */
.compare-table-hint {
  display: none;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-terracotta);
  margin-bottom: 8px;
  text-align: right;
}

@media (max-width: 768px) {
  .compare-table-hint {
    display: block;
  }
}

.payment-method-box {
  background: var(--bg-paper);
  border: 1.5px solid var(--border-paper);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}

.payment-method-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.payment-method-icon {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-sm);
  background: var(--color-terracotta);
  color: #FFF;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1rem;
}

/* SECTION 17: FOOTER */
.site-footer {
  background: #050403;
  color: var(--text-light-muted);
  padding: 56px 0 40px;
  border-top: 1px solid var(--bg-dark-border);
  font-size: 0.9rem;
  line-height: 1.7;
}

.footer-brand {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-light-primary);
  margin-bottom: 16px;
}

.footer-disclaimer {
  max-width: 860px;
  margin-bottom: 24px;
}

.footer-disclaimer p {
  margin-bottom: 8px;
}

/* ===================================================================
   SEPAY VIETQR PAYMENT MODAL
   =================================================================== */
.qr-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(11, 9, 8, 0.88);
  backdrop-filter: blur(8px);
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.qr-modal-content {
  background: #FFF;
  border: 2px solid var(--text-dark-primary);
  border-radius: var(--radius-md);
  max-width: 520px;
  width: 100%;
  max-height: 92vh;
  overflow-y: auto;
  box-shadow: 12px 12px 0px var(--color-terracotta);
  padding: 32px 28px;
  position: relative;
  animation: modalPop 0.3s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes modalPop {
  0% { opacity: 0; transform: scale(0.92) translateY(20px); }
  100% { opacity: 1; transform: scale(1) translateY(0); }
}

.qr-modal-close {
  position: absolute;
  top: 20px;
  right: 20px;
  width: 36px;
  height: 36px;
  border: 1.5px solid var(--text-dark-primary);
  border-radius: var(--radius-sm);
  background: #FFF;
  color: var(--text-dark-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-weight: 900;
  font-size: 1.2rem;
  transition: all 0.2s ease;
}

.qr-modal-close:hover {
  background: var(--text-dark-primary);
  color: #FFF;
}

.qr-image-wrap {
  background: #F9F7F4;
  border: 1.5px solid var(--border-paper);
  border-radius: var(--radius-sm);
  padding: 16px;
  text-align: center;
  margin: 20px 0;
}

.qr-img {
  max-width: 240px;
  width: 100%;
  height: auto;
  display: block;
  margin: 0 auto;
  border-radius: 4px;
}

.bank-detail-table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 0.95rem;
}

.bank-detail-table tr {
  border-bottom: 1px solid var(--border-paper);
}

.bank-detail-table td {
  padding: 10px 0;
}

.bank-detail-table td:first-child {
  color: var(--text-dark-muted);
  width: 38%;
}

.bank-detail-table td:last-child {
  font-weight: 700;
  color: var(--text-dark-primary);
  text-align: right;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}

.copy-btn {
  background: var(--bg-paper);
  border: 1px solid var(--border-paper-dark);
  border-radius: var(--radius-sm);
  padding: 3px 8px;
  font-size: 0.78rem;
  font-family: var(--font-body);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
}

.copy-btn:hover {
  background: var(--color-terracotta);
  color: #FFF;
  border-color: var(--color-terracotta);
}

.qr-poll-status {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px;
  background: rgba(184, 85, 47, 0.08);
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--color-terracotta);
  margin-top: 16px;
}

.qr-spinner {
  width: 18px;
  height: 18px;
  border: 2px solid rgba(184, 85, 47, 0.25);
  border-top-color: var(--color-terracotta);
  border-radius: 50%;
  animation: qrSpin 0.8s linear infinite;
}

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

/* Sticky Action Bar (appears on scroll) */
.sticky-cta-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(11, 9, 8, 0.95);
  border-top: 1.5px solid var(--bg-dark-border);
  padding: 12px 24px;
  z-index: 90;
  backdrop-filter: blur(10px);
  transform: translateY(120%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.sticky-cta-bar.visible {
  transform: translateY(0);
}

.sticky-cta-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.sticky-price-info {
  display: flex;
  align-items: baseline;
  gap: 14px;
  min-width: 0;
}

.sticky-course-name {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--text-light-primary);
  white-space: nowrap;
  letter-spacing: 0.02em;
}

.sticky-amount-group {
  display: flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
}

.sticky-amount {
  font-family: var(--font-display);
  font-size: 1.65rem;
  font-weight: 900;
  color: var(--color-terracotta);
  line-height: 1;
  white-space: nowrap;
}

.sticky-sub {
  font-family: var(--font-body);
  font-size: 0.88rem;
  color: var(--text-light-muted);
  white-space: nowrap;
}

.sticky-dot {
  display: inline;
}

/* ===================================================================
   THANK YOU PAGE STYLES
   =================================================================== */
.ty-wrap {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--bg-paper);
  color: var(--text-dark-primary);
}

.ty-header {
  background: var(--bg-dark);
  color: var(--text-light-primary);
  padding: 60px 24px;
  text-align: center;
  border-bottom: 3px solid var(--color-terracotta);
}

.ty-container {
  max-width: 800px;
  margin: -30px auto 60px;
  padding: 0 20px;
  width: 100%;
}

.ty-main-card {
  background: #FFF;
  border: 2px solid var(--text-dark-primary);
  border-radius: var(--radius-md);
  padding: 40px 36px;
  box-shadow: 8px 8px 0px var(--text-dark-primary);
}

.ty-step-box {
  background: var(--bg-paper);
  border: 1.5px solid var(--border-paper);
  border-radius: var(--radius-md);
  padding: 24px 26px;
  margin: 20px 0;
}

.ty-step-title {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--color-terracotta);
  margin-bottom: 10px;
}

.ty-action-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 16px 36px;
  font-family: var(--font-display);
  font-size: 1.45rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: var(--color-terracotta);
  color: #FFF;
  border: 2px solid var(--color-terracotta-dark);
  border-radius: var(--radius-sm);
  text-decoration: none;
  margin-top: 12px;
  transition: all 0.2s ease;
  box-shadow: 0 6px 20px rgba(184, 85, 47, 0.3);
}

.ty-action-btn:hover {
  background: var(--color-terracotta-hover);
  transform: translateY(-2px);
}

.ty-zalo-btn {
  background: var(--color-slate);
  border-color: var(--color-slate-light);
  box-shadow: 0 6px 20px rgba(44, 74, 92, 0.3);
}

.ty-zalo-btn:hover {
  background: var(--color-slate-light);
}

/* ===================================================================
   RESPONSIVE MOBILE BREAKPOINTS (A-Z OPTIMIZATION)
   =================================================================== */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .problem-grid,
  .prereq-grid,
  .instructor-wrap,
  .project-focus-wrap,
  .audience-grid,
  .checkout-section-wrap {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .instructor-photo-card {
    max-width: 320px;
    margin: 0 auto;
  }

  .compare-table {
    min-width: 560px;
  }

  .compare-table-wrap {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
}

@media (max-width: 640px) {
  .section {
    padding: 56px 0;
  }

  .container, .container-narrow {
    padding-left: 16px;
    padding-right: 16px;
  }

  .top-bar {
    padding: 10px 0;
  }

  .top-bar-inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
  }

  .top-bar-logo {
    height: 28px;
    max-width: 115px;
  }

  .brand-divider,
  .brand-course-tag,
  .brand-author {
    display: none;
  }

  .top-bar-actions {
    display: flex;
    align-items: center;
    gap: 8px;
  }

  .top-bar-cta {
    padding: 6px 14px;
    font-size: 0.92rem;
    min-height: 38px;
    white-space: nowrap;
  }

  .hero-wrap {
    padding: 24px 0 44px;
  }

  .hero-header-center {
    margin-bottom: 32px;
  }

  .hero-brand-badge {
    padding: 5px 12px;
    gap: 8px;
    margin-bottom: 14px;
  }

  .hero-brand-logo {
    height: 20px;
    max-width: 90px;
  }

  .hero-badge-tag {
    font-size: 0.78rem;
    padding-left: 8px;
  }


  .hero-headline-br {
    display: inline;
  }

  .headline-huge {
    font-size: clamp(2.2rem, 9vw, 3.2rem);
    line-height: 1.18;
    word-break: break-word;
  }

  .headline-large {
    font-size: clamp(1.85rem, 7vw, 2.6rem);
    line-height: 1.25;
    word-break: break-word;
  }

  .headline-medium {
    font-size: clamp(1.4rem, 5.5vw, 1.9rem);
    line-height: 1.25;
  }

  .pricing-pillars {
    font-size: 0.95rem;
    padding: 12px 14px;
    gap: 6px;
  }

  .editorial-quote {
    padding: 18px 20px;
    font-size: 1.1rem;
    margin: 24px 0;
  }

  .btn-cta {
    width: 100%;
    padding: 16px 20px;
    min-height: 52px;
    font-size: 1.3rem;
  }

  .btn-cta-sub {
    font-size: 0.95rem;
  }

  /* Form inputs: 16px font-size prevents iOS Safari automatic zoom */
  .form-input {
    font-size: 16px;
    padding: 12px 14px;
  }

  .sticky-cta-bar {
    padding: 8px 16px max(10px, env(safe-area-inset-bottom));
    background: rgba(11, 9, 8, 0.96);
    border-top: 1px solid rgba(184, 85, 47, 0.3);
    box-shadow: 0 -4px 24px rgba(0, 0, 0, 0.6);
  }

  .sticky-cta-inner {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
  }

  .sticky-price-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    gap: 10px;
  }

  .sticky-course-name {
    font-size: 1.05rem;
    font-weight: 800;
    white-space: nowrap;
    letter-spacing: 0.02em;
    flex-shrink: 0;
  }

  .sticky-amount-group {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 1px;
    white-space: nowrap;
    flex-shrink: 0;
  }

  .sticky-amount {
    font-size: 1.35rem;
    line-height: 1;
    color: var(--color-terracotta);
    font-weight: 900;
    white-space: nowrap;
  }

  .sticky-sub {
    font-size: 0.72rem;
    color: var(--text-light-muted);
    line-height: 1.2;
    white-space: nowrap;
  }

  .sticky-dot {
    display: none;
  }

  .sticky-cta-btn {
    width: 100%;
    text-align: center;
    padding: 11px 16px;
    font-size: 1.15rem;
    letter-spacing: 0.04em;
    border-radius: var(--radius-sm);
    box-shadow: 0 4px 14px rgba(184, 85, 47, 0.35);
  }

  @media (max-width: 375px) {
    .sticky-cta-bar {
      padding: 6px 12px max(8px, env(safe-area-inset-bottom));
    }
    .sticky-course-name {
      font-size: 0.95rem;
    }
    .sticky-amount {
      font-size: 1.22rem;
    }
    .sticky-sub {
      font-size: 0.68rem;
    }
    .sticky-cta-btn {
      padding: 10px 12px;
      font-size: 1.05rem;
    }
  }

  .compare-table {
    min-width: 520px;
  }

  .compare-table th, .compare-table td {
    padding: 10px 12px;
    font-size: 0.88rem;
  }

  .final-cta-wrap {
    padding: 32px 16px;
  }

  .order-form-card, .order-summary-card {
    padding: 20px 16px;
  }

  /* QR Modal on Mobile */
  .qr-modal {
    padding: 12px;
    align-items: flex-end;
  }

  .qr-modal-content {
    padding: 24px 16px 20px;
    max-height: 92vh;
    border-radius: var(--radius-md);
    box-shadow: 6px 6px 0px var(--color-terracotta);
  }

  .qr-image-wrap {
    margin: 14px 0;
    padding: 12px;
  }

  .qr-img {
    max-width: 190px;
  }

  .bank-detail-table {
    font-size: 0.88rem;
    margin: 12px 0;
  }

  .bank-detail-table td {
    padding: 8px 0;
  }

  .bank-detail-table td:last-child {
    font-size: 0.88rem;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 6px;
  }

  .copy-btn {
    padding: 4px 10px;
    font-size: 0.78rem;
    min-height: 32px;
  }

  /* Thank You Page Mobile */
  .ty-header {
    padding: 40px 16px 28px;
  }

  .ty-container {
    margin: -15px auto 40px;
    padding: 0 14px;
  }

  .ty-main-card {
    padding: 24px 16px;
    box-shadow: 4px 4px 0px var(--text-dark-primary);
  }

  .ty-step-box {
    padding: 18px 16px;
    margin: 16px 0;
  }

  .ty-action-btn {
    width: 100%;
    padding: 14px 20px;
    font-size: 1.25rem;
    min-height: 48px;
  }
}

@media (max-width: 380px) {
  .headline-huge {
    font-size: 2.1rem;
    line-height: 1.2;
  }

  .headline-large {
    font-size: 1.75rem;
    line-height: 1.25;
  }

  .container, .container-narrow {
    padding-left: 12px;
    padding-right: 12px;
  }
}

/* ===================================================================
   UI/UX PRO MAX — ACCESSIBILITY, MICRO-INTERACTIONS & POLISH
   =================================================================== */

/* SVG Icon Utilities */
.ui-icon {
  display: inline-block;
  vertical-align: middle;
  flex-shrink: 0;
}

.icon-terracotta {
  stroke: var(--color-terracotta);
}

/* Hero guarantee row with SVG icons */
.hero-guarantee-note {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px 16px;
  font-size: 0.88rem;
  color: var(--text-light-secondary);
  margin-top: 14px;
}

.hero-guarantee-item {
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

/* Order summary feature lines with SVG icon */
.order-feature-line {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-bottom: 8px;
  font-size: 0.95rem;
  color: var(--text-light-secondary);
  line-height: 1.6;
}

.order-feature-line svg {
  margin-top: 3px;
  flex-shrink: 0;
}

.order-feature-line:last-child {
  margin-bottom: 0;
}

/* Password reminder icon alignment */
.password-reminder-icon {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  margin-top: 1px;
}

/* form-input: 16px prevents iOS Safari auto-zoom */
.form-input {
  font-size: 16px !important;
}

/* Focus-visible ring for keyboard navigation */
.form-input:focus-visible {
  outline: 2px solid var(--color-terracotta);
  outline-offset: 2px;
}

.btn-cta:focus-visible,
.top-bar-cta:focus-visible,
.ty-action-btn:focus-visible,
.faq-header:focus-visible {
  outline: 2px solid var(--color-terracotta);
  outline-offset: 3px;
}

/* Cursor pointer on all interactive cards */
.preview-card,
.loop-step-card,
.milestone-card,
.obstacle-card,
.deliverable-card,
.audience-card,
.faq-item,
.faq-header {
  cursor: pointer;
}

/* Deliverable card hover */
.deliverable-card {
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1),
              box-shadow 0.2s ease,
              border-color 0.2s ease;
}

.deliverable-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 14px 32px -8px rgba(20, 16, 13, 0.12);
  border-color: var(--color-terracotta);
}

/* Obstacle card smoother transition */
.obstacle-card {
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1),
              border-color 0.2s ease;
}

/* Milestone card smoother transition */
.milestone-card {
  transition: border-color 0.2s ease, transform 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.milestone-card:hover {
  transform: translateY(-2px);
}

/* Audience card hover */
.audience-card {
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.2s ease;
}

.audience-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 14px 32px -8px rgba(20, 16, 13, 0.12);
}

/* FAQ item cursor pointer already on .faq-header, stabilize */
.faq-item {
  cursor: default;
}

.faq-header {
  cursor: pointer;
  transition: background-color 0.18s ease;
}

.faq-header:hover {
  background-color: rgba(244, 237, 227, 0.04);
}

/* Compare table: highlight "Sản phẩm thật" column more strongly */
.compare-table th:nth-child(3) {
  background: rgba(184, 85, 47, 0.08);
  border-top: 3px solid var(--color-terracotta);
}

.compare-table td:nth-child(3) {
  background: rgba(184, 85, 47, 0.05);
  border-right: 2px solid rgba(184, 85, 47, 0.2);
  border-left: 2px solid rgba(184, 85, 47, 0.2);
}

/* Scroll-stable hover: prevent layout shift on cards with shadows */
.preview-card,
.loop-step-card,
.deliverable-card,
.audience-card {
  will-change: transform;
}

/* top-bar CTA smoother cubic transition */
.top-bar-cta {
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Password toggle button focus-visible */
.password-toggle-btn:focus-visible {
  outline: 2px solid var(--color-terracotta);
  outline-offset: 2px;
}

/* Sticky CTA button base */
.sticky-cta-btn {
  cursor: pointer;
  padding: 12px 28px;
  font-size: 1.2rem;
  white-space: nowrap;
  flex-shrink: 0;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}
.sticky-cta-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(184, 85, 47, 0.5);
}

/* ===================================================================
   SECTION: SẢN PHẨM ĐANG HOẠT ĐỘNG (REAL PRODUCTS SHOWCASE)
   =================================================================== */
.live-products-header {
  max-width: 900px;
  margin-bottom: 36px;
}

.live-badge-wrapper {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
}

.live-status-dot-pulse {
  width: 8px;
  height: 8px;
  background-color: #22C55E;
  border-radius: 50%;
  display: inline-block;
  box-shadow: 0 0 0 0 rgba(34, 197, 94, 0.7);
  animation: pulseGreenGlow 2s infinite;
}

@keyframes pulseGreenGlow {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(34, 197, 94, 0.7); }
  70% { transform: scale(1); box-shadow: 0 0 0 7px rgba(34, 197, 94, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(34, 197, 94, 0); }
}

.live-products-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 3.8vw, 3rem);
  line-height: 1.15;
  letter-spacing: 0.02em;
  text-wrap: balance;
  margin: 0 0 14px 0;
}

.live-products-subtitle {
  font-size: 1.16rem;
  line-height: 1.7;
  color: var(--text-dark-secondary);
  margin: 0;
  max-width: 820px;
}

.live-products-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 26px;
  margin-top: 10px;
}

.live-product-card {
  background: #FFFFFF;
  border: 2px solid #1E1D1B;
  border-radius: 14px;
  padding: 30px 28px 24px;
  box-shadow: 5px 5px 0px #1E1D1B;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.22s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.22s ease, border-color 0.22s ease;
  position: relative;
}

.live-product-card:hover {
  transform: translateY(-4px);
  box-shadow: 7px 7px 0px #B75632;
  border-color: #B75632;
}

.live-card-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  padding-bottom: 14px;
  border-bottom: 1px solid #EAE5DE;
}

.live-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: #166534;
  background: #DCFCE7;
  border: 1px solid #BBF7D0;
  padding: 3px 9px;
  border-radius: 999px;
}

.pulse-dot {
  width: 7px;
  height: 7px;
  background-color: #22C55E;
  border-radius: 50%;
  display: inline-block;
  animation: pulseGreenGlow 2s infinite;
}

.live-cat-badge {
  font-family: var(--font-body);
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: #B75632;
  background: rgba(183, 86, 50, 0.08);
  border: 1px solid rgba(183, 86, 50, 0.2);
  padding: 3px 8px;
  border-radius: 5px;
  text-transform: uppercase;
}

.live-product-identity {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 18px;
  margin-bottom: 12px;
}

.live-product-icon-box {
  width: 52px;
  height: 52px;
  background: #1E1D1B;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.08);
}

.live-product-info {
  flex: 1;
  min-width: 0;
}

.live-product-name {
  font-family: var(--font-display);
  font-size: 1.95rem;
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: 0.03em;
  color: #1E1D1B;
  margin: 0 0 4px 0;
}

.live-domain-badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.85rem;
  color: #716E69;
  font-weight: 500;
  font-family: var(--font-mono, monospace);
}

.live-product-desc {
  font-size: 1.02rem;
  line-height: 1.6;
  color: #383531;
  margin: 0 0 16px 0;
  min-height: 48px;
}

.live-chips-row {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin-bottom: 22px;
}

.live-chip-item {
  font-size: 0.8rem;
  font-weight: 600;
  color: #4A4641;
  background: #F4EFEA;
  border: 1px solid #E2DCD5;
  padding: 4px 9px;
  border-radius: 6px;
}

.live-product-btn {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 12px 18px;
  background: #1E1D1B;
  color: #FFFFFF !important;
  font-family: var(--font-display);
  font-size: 1.12rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  text-decoration: none !important;
  border-radius: 8px;
  border: 1.5px solid #1E1D1B;
  transition: all 0.2s ease;
  box-sizing: border-box;
}

.btn-arrow-circle {
  width: 28px;
  height: 28px;
  background: rgba(255,255,255,0.12);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.2s ease, background 0.2s ease;
}

.live-product-btn:hover {
  background: #B75632;
  border-color: #B75632;
  color: #FFFFFF !important;
  box-shadow: 0 6px 16px rgba(183, 86, 50, 0.35);
  transform: translateY(-2px);
}

.live-product-btn:hover .btn-arrow-circle {
  background: rgba(255,255,255,0.25);
  transform: translate(2px, -2px);
}

@media (max-width: 860px) {
  .live-products-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }
  .live-product-card {
    padding: 22px 20px 20px;
  }
  .live-product-desc {
    min-height: auto;
  }
}