:root {
  --bg-primary: #0b0d13;
  --bg-secondary: #11151f;
  --bg-card: #171b26;
  --bg-card-hover: #1e2433;
  --bg-elevated: #202635;
  --text-primary: #f9fafb;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;
  --brand-red: #ff3b5c;
  --brand-red-hover: #e11d48;
  --brand-red-soft: rgba(255, 59, 92, 0.14);
  --accent-green: #10b981;
  --accent-green-soft: rgba(16, 185, 129, 0.14);
  --accent-amber: #f59e0b;
  --border-color: #262c3a;
  --border-highlight: #374151;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 12px 32px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 20px 48px rgba(0, 0, 0, 0.65);
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
  --container-max: 1200px;
}

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

html {
  scroll-behavior: smooth;
  font-family: "Be Vietnam Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  line-height: 1.65;
  color-scheme: dark;
}

body {
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: var(--bg-primary);
  color: var(--text-primary);
}

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

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

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 20px;
}

/* Header & Navbar - Strict Single-Line No-Wrap */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 13, 19, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-color);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 16px;
  flex-wrap: nowrap;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.2rem;
  letter-spacing: -0.02em;
  white-space: nowrap;
  flex-shrink: 0;
  color: var(--text-primary);
}

.brand-logo img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  box-shadow: var(--shadow-sm);
  flex-shrink: 0;
}

.brand-badge {
  font-size: 0.7rem;
  font-weight: 700;
  background: var(--brand-red-soft);
  color: var(--brand-red);
  border: 1px solid rgba(255, 59, 92, 0.28);
  padding: 2px 8px;
  border-radius: 999px;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-secondary);
  white-space: nowrap;
  flex-wrap: nowrap;
}

.nav-links a {
  white-space: nowrap;
  padding: 6px 2px;
  transition: color 0.15s ease;
}

.nav-links a:hover {
  color: var(--text-primary);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  white-space: nowrap;
}

.lang-switch {
  display: inline-flex;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 999px;
  padding: 3px;
  flex-shrink: 0;
}

.lang-btn {
  border: none;
  background: transparent;
  padding: 5px 11px;
  border-radius: 999px;
  font-family: inherit;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.lang-btn.active {
  background: var(--brand-red);
  color: #ffffff;
}

/* Google Play Buttons */
.btn-play-nav {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--bg-elevated);
  color: var(--text-primary);
  border: 1px solid var(--border-highlight);
  font-weight: 700;
  font-size: 0.88rem;
  padding: 8px 15px;
  border-radius: 999px;
  white-space: nowrap;
  flex-shrink: 0;
  transition: all 0.15s ease;
}

.btn-play-nav:hover {
  background: #283044;
  border-color: var(--brand-red);
  transform: translateY(-1px);
}

.play-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.play-icon-lg {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

.btn-play-hero {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: #ffffff;
  color: #0b0d13;
  padding: 11px 22px;
  border-radius: 14px;
  font-weight: 700;
  white-space: nowrap;
  box-shadow: 0 8px 24px rgba(255, 255, 255, 0.12);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.btn-play-hero:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(255, 255, 255, 0.2);
}

.btn-play-text {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  line-height: 1.15;
}

.btn-play-sub {
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: #4b5563;
}

.btn-play-main {
  font-size: 1.05rem;
  font-weight: 800;
  color: #0b0d13;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  font-weight: 700;
  font-size: 0.95rem;
  padding: 13px 22px;
  border-radius: 14px;
  white-space: nowrap;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-highlight);
}

/* Hero Section */
.hero-section {
  padding: 64px 0 56px;
  background: radial-gradient(circle at 75% 25%, rgba(255, 59, 92, 0.12) 0%, rgba(16, 185, 129, 0.05) 35%, transparent 70%),
              linear-gradient(180deg, #0b0d13 0%, #11151f 100%);
  border-bottom: 1px solid var(--border-color);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

.trust-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 999px;
  padding: 6px 14px;
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 20px;
  box-shadow: var(--shadow-sm);
}

.trust-pill .stars {
  color: var(--accent-amber);
}

.hero-title {
  font-size: clamp(2.1rem, 3.8vw, 3.15rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 18px;
  color: var(--text-primary);
}

.hero-title .highlight {
  color: var(--brand-red);
}

.hero-subtitle {
  font-size: 1.06rem;
  color: var(--text-secondary);
  margin-bottom: 28px;
  max-width: 590px;
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-bottom: 32px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

.stat-item strong {
  display: block;
  font-size: 1.45rem;
  font-weight: 800;
  color: var(--text-primary);
}

.stat-item span {
  font-size: 0.84rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.hero-visual {
  display: flex;
  justify-content: center;
  position: relative;
}

.hero-phone-card {
  width: 100%;
  max-width: 340px;
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-highlight);
  background: var(--bg-card);
}

/* Section Generic */
.section {
  padding: 76px 0;
}

.section-alt {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  max-width: 740px;
  margin: 0 auto 48px;
}

.section-eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--brand-red);
  background: var(--brand-red-soft);
  border: 1px solid rgba(255, 59, 92, 0.25);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(1.7rem, 2.8vw, 2.35rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.25;
  margin-bottom: 14px;
  color: var(--text-primary);
}

.section-desc {
  font-size: 1.02rem;
  color: var(--text-secondary);
}

/* Screenshot Gallery (8 x 9:16 Dark Mode Previews) */
.screenshot-track {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}

.screenshot-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
}

.screenshot-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-highlight);
  box-shadow: var(--shadow-md);
}

.screenshot-img-wrap {
  aspect-ratio: 9 / 16;
  width: 100%;
  background: #0f1117;
  overflow: hidden;
  position: relative;
}

.screenshot-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.screenshot-caption {
  padding: 16px;
  border-top: 1px solid var(--border-color);
  background: var(--bg-card);
  flex: 1;
}

.screenshot-step {
  font-size: 0.72rem;
  font-weight: 800;
  color: var(--brand-red);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.screenshot-caption h3 {
  font-size: 1rem;
  font-weight: 700;
  margin: 4px 0 6px;
  color: var(--text-primary);
}

.screenshot-caption p {
  font-size: 0.86rem;
  color: var(--text-secondary);
}

/* Feature Bento Grid (11+ Tools) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 26px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: border-color 0.2s ease;
}

.feature-card:hover {
  border-color: var(--border-highlight);
}

.feature-card.featured {
  border-color: rgba(255, 59, 92, 0.35);
  background: linear-gradient(180deg, rgba(255, 59, 92, 0.09) 0%, var(--bg-card) 45%);
}

.feature-icon {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1.35rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border-color);
}

.feature-card.featured .feature-icon {
  background: var(--brand-red);
  border-color: var(--brand-red);
  color: #ffffff;
}

.feature-badge {
  display: inline-block;
  align-self: flex-start;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 2px 10px;
  border-radius: 999px;
  background: var(--accent-green-soft);
  color: var(--accent-green);
  border: 1px solid rgba(16, 185, 129, 0.25);
}

.feature-card h3 {
  font-size: 1.14rem;
  font-weight: 800;
  color: var(--text-primary);
}

.feature-card p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  flex: 1;
}

.feature-benefit {
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--accent-green);
  padding-top: 12px;
  border-top: 1px dashed var(--border-color);
}

/* AI Thumbnail Showcase Strip */
.thumb-showcase {
  margin-top: 40px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
}

.thumb-showcase-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 20px;
}

.thumb-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.thumb-item {
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-color);
  background: var(--bg-secondary);
}

.thumb-item img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.thumb-item span {
  display: block;
  padding: 10px 12px;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-secondary);
}

/* Social Proof & Play Store Reviews */
.reviews-summary-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  margin-bottom: 32px;
  box-shadow: var(--shadow-sm);
}

.rating-big {
  display: flex;
  align-items: center;
  gap: 20px;
}

.rating-number {
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1;
  color: var(--text-primary);
}

.rating-stars {
  color: var(--accent-amber);
  font-size: 1.25rem;
  letter-spacing: 2px;
}

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 16px;
}

.review-stars {
  color: var(--accent-amber);
  font-size: 0.95rem;
}

.review-text {
  font-size: 0.94rem;
  color: var(--text-primary);
  font-style: italic;
}

.review-author {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-color);
  padding-top: 12px;
}

.review-author strong {
  color: var(--text-primary);
}

.verified-badge {
  color: var(--accent-green);
  font-weight: 700;
  font-size: 0.78rem;
}

/* FAQ / Q&A Section */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.faq-item summary {
  padding: 20px 24px;
  font-weight: 700;
  font-size: 1.02rem;
  color: var(--text-primary);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

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

.faq-item summary::after {
  content: "+";
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--brand-red);
  flex-shrink: 0;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-answer {
  padding: 14px 24px 20px;
  color: var(--text-secondary);
  font-size: 0.94rem;
  border-top: 1px solid var(--border-color);
}

/* Bottom CTA Banner */
.cta-banner {
  background: linear-gradient(135deg, #171b26 0%, #1e1524 100%);
  border: 1px solid var(--border-highlight);
  color: var(--text-primary);
  border-radius: var(--radius-xl);
  padding: 56px 40px;
  text-align: center;
  box-shadow: var(--shadow-lg);
}

.cta-banner h2 {
  font-size: clamp(1.75rem, 3vw, 2.4rem);
  font-weight: 800;
  margin-bottom: 14px;
}

.cta-banner p {
  color: var(--text-secondary);
  font-size: 1.04rem;
  max-width: 620px;
  margin: 0 auto 28px;
}

/* Footer */
.site-footer {
  background: #07090e;
  border-top: 1px solid var(--border-color);
  color: var(--text-secondary);
  padding: 56px 0 36px;
  font-size: 0.9rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 36px;
  margin-bottom: 40px;
}

.footer-brand {
  color: var(--text-primary);
  font-weight: 800;
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.footer-brand img {
  width: 34px;
  height: 34px;
  border-radius: 8px;
}

.footer-col h4 {
  color: var(--text-primary);
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 14px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-col a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* Bilingual Helper */
[data-lang="vi"] {
  display: none;
}

body.lang-vi [data-lang="en"] {
  display: none !important;
}

body.lang-vi [data-lang="vi"] {
  display: revert !important;
}

/* Responsive */
@media (max-width: 1024px) {
  .screenshot-track {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
  }
  .hero-cta-group {
    justify-content: center;
  }
  .features-grid,
  .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .thumb-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .nav-links {
    display: none;
  }
}

@media (max-width: 600px) {
  .screenshot-track,
  .features-grid,
  .reviews-grid,
  .hero-stats,
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .brand-badge {
    display: none;
  }
  .cta-banner {
    padding: 36px 20px;
  }
}