/* ═══════════════════════════════════════════
   RetroLab Portfolio — White Theme
   Matching retrolab.com.vn live site
   BG:      #f0f2f8 (soft blue-gray)
   Surface: #ffffff (white cards)
   Primary: #2563eb (royal blue)
   Accent:  #ef4444 (red category badges)
   Text:    #1e293b / #64748b
   ═══════════════════════════════════════════ */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: #f0f2f8;
  color: #1e293b;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

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

/* ── Utilities ─────────────────────────────── */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2rem);
}

.gradient-text {
  background: linear-gradient(135deg, #2563eb 0%, #3b82f6 50%, #60a5fa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.gradient-text-alt {
  background: linear-gradient(135deg, #059669 0%, #10b981 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ── Navigation — matches retrolab.com.vn ──── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px) saturate(1.8);
  -webkit-backdrop-filter: blur(20px) saturate(1.8);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transition: all 0.3s ease;
}

.nav.scrolled {
  background: rgba(255, 255, 255, 0.97);
  box-shadow: 0 1px 20px rgba(0, 0, 0, 0.06);
}

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #1e293b;
}

.logo-svg {
  flex-shrink: 0;
}

.logo-accent {
  color: #2563eb;
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-link {
  font-size: 14px;
  font-weight: 600;
  color: #475569;
  transition: color 0.2s;
  position: relative;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: #2563eb;
  border-radius: 1px;
  transition: width 0.3s ease;
}

.nav-link:hover {
  color: #2563eb;
}

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

.nav-link.active {
  color: #2563eb;
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  background: #2563eb;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  color: white;
  transition: all 0.25s ease;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.25);
}

.nav-cta:hover {
  background: #1d4ed8;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.35);
}

/* ── Hero Section — light gradient ─────────── */
.hero {
  position: relative;
  min-height: 100vh;
  padding: 120px 0 60px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
  background: #f0f2f8;
}

.hero-bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(37, 99, 235, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 70% at 50% 30%, black 0%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 80% 70% at 50% 30%, black 0%, transparent 100%);
}

.hero-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  pointer-events: none;
}

.hero-glow-1 {
  width: 600px;
  height: 600px;
  background: rgba(37, 99, 235, 0.08);
  top: -200px;
  left: -100px;
  animation: float-slow 25s ease-in-out infinite;
}

.hero-glow-2 {
  width: 500px;
  height: 500px;
  background: rgba(250, 204, 21, 0.06);
  top: -100px;
  right: -150px;
  animation: float-slow 20s ease-in-out infinite reverse;
}

.hero-glow-3 {
  width: 400px;
  height: 400px;
  background: rgba(37, 99, 235, 0.05);
  bottom: 100px;
  left: 30%;
  animation: float-slow 22s ease-in-out infinite 5s;
}

@keyframes float-slow {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(30px, -20px) scale(1.05); }
  66% { transform: translate(-20px, 15px) scale(0.95); }
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2rem);
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 100px;
  font-size: 13px;
  font-weight: 600;
  color: #2563eb;
  margin-bottom: 2rem;
  animation: fade-slide-up 0.6s ease-out;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.badge-dot {
  width: 6px;
  height: 6px;
  background: #22c55e;
  border-radius: 50%;
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.3); }
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.2rem);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.03em;
  color: #0f172a;
  margin-bottom: 1.5rem;
  animation: fade-slide-up 0.6s ease-out 0.1s both;
}

.hero-line {
  display: block;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.15rem);
  color: #64748b;
  max-width: 680px;
  margin: 0 auto 2rem;
  line-height: 1.8;
  animation: fade-slide-up 0.6s ease-out 0.2s both;
}

.hero-subtitle strong {
  color: #1e293b;
  font-weight: 600;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  margin-bottom: 3rem;
  animation: fade-slide-up 0.6s ease-out 0.3s both;
}

/* ── Buttons — matching retrolab.com.vn ────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all 0.25s ease;
  text-decoration: none;
}

.btn-primary {
  background: #2563eb;
  color: white;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
  background: #1d4ed8;
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.4);
}

.btn-ghost {
  background: white;
  border: 1px solid #e2e8f0;
  color: #475569;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.04);
}

.btn-ghost:hover {
  background: #f8fafc;
  border-color: #cbd5e1;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}

.btn-lg {
  padding: 14px 32px;
  font-size: 15px;
  border-radius: 12px;
}

/* ── Hero Stats — white cards like retrolab ── */
.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  padding: 1.5rem 2.5rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
  animation: fade-slide-up 0.6s ease-out 0.4s both;
}

.stat {
  text-align: center;
}

.stat-number {
  display: block;
  font-size: 2rem;
  font-weight: 800;
  color: #0f172a;
  letter-spacing: -0.02em;
  font-family: 'JetBrains Mono', 'Inter', monospace;
}

.stat-suffix {
  font-size: 1.5rem;
  font-weight: 700;
  color: #2563eb;
}

.stat-label {
  font-size: 12px;
  font-weight: 500;
  color: #94a3b8;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 2px;
}

.stat-divider {
  width: 1px;
  height: 40px;
  background: #e2e8f0;
}

/* ── Hero Screenshot — matching retrolab.com.vn card style ── */
.hero-screenshot-container {
  position: relative;
  margin-top: 4rem;
  padding: 0 clamp(1rem, 4vw, 2rem);
  max-width: 1100px;
  width: 100%;
  animation: fade-slide-up 0.8s ease-out 0.5s both;
}

.screenshot-frame {
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid #e2e8f0;
  background: white;
  box-shadow:
    0 20px 60px rgba(0, 0, 0, 0.08),
    0 8px 20px rgba(0, 0, 0, 0.04);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.screenshot-frame:hover {
  transform: translateY(-4px);
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.1),
    0 12px 30px rgba(0, 0, 0, 0.06);
}

.frame-dark {
  background: #0f172a;
  border-color: rgba(255, 255, 255, 0.1);
}

.frame-dark .frame-header {
  background: #0c1322;
  border-bottom-color: rgba(255, 255, 255, 0.06);
}

.frame-dark .frame-url {
  color: #64748b;
}

.frame-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: #f8fafc;
  border-bottom: 1px solid #e2e8f0;
}

.frame-dots {
  display: flex;
  gap: 6px;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.dot-red { background: #ef4444; }
.dot-yellow { background: #eab308; }
.dot-green { background: #22c55e; }

.frame-url {
  font-size: 12px;
  font-weight: 500;
  color: #94a3b8;
  font-family: 'JetBrains Mono', monospace;
}

.screenshot-img {
  width: 100%;
  display: block;
}

.screenshot-glow {
  position: absolute;
  bottom: -50px;
  left: 10%;
  right: 10%;
  height: 200px;
  background: radial-gradient(ellipse, rgba(37, 99, 235, 0.06) 0%, transparent 70%);
  pointer-events: none;
}

/* ── Sections ──────────────────────────────── */
.section {
  padding: clamp(2.5rem, 6vw, 4rem) 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 4rem;
}

.section-label {
  display: inline-block;
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #ef4444;
  background: rgba(239, 68, 68, 0.08);
  padding: 5px 14px;
  border-radius: 4px;
  margin-bottom: 1rem;
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  color: #0f172a;
  margin-bottom: 1rem;
}

.section-desc {
  font-size: 1.05rem;
  color: #64748b;
  line-height: 1.7;
}

/* ── Overview / Problem Section ────────────── */
.section-overview {
  background: #f0f2f8;
}



.problems-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-bottom: 4rem;
}

.problem-card {
  padding: 2.5rem 2rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
  transition: all 0.3s ease;
}

.problem-card:hover {
  border-color: #cbd5e1;
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}


.problem-card h3 {
  font-size: 1.25rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 0.5rem;
}

.problem-card p {
  font-size: 0.95rem;
  color: #64748b;
  line-height: 1.6;
}

/* Solution Banner — Split Composition but Soft Styling */
.solution-banner {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 20px;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
}

.solution-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 0;
}

.solution-text {
  padding: 4rem 3rem;
}

.solution-text .solution-label {
  display: inline-block;
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #22c55e;
  background: rgba(34, 197, 94, 0.1);
  padding: 4px 12px;
  border-radius: 4px;
  margin-bottom: 1.5rem;
}

.solution-text h3 {
  font-size: 2rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.solution-text p {
  font-size: 1.05rem;
  color: #475569;
  line-height: 1.7;
}

.solution-metrics {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  padding: 4rem 3rem;
  background: #0f172a; /* Keep the dark right side for contrast */
  justify-content: center;
}

.metric {
  text-align: left;
  padding: 0;
  background: transparent;
  border: none;
  border-radius: 0;
}

.metric-value {
  display: block;
  font-size: 2.5rem;
  font-weight: 800;
  font-family: 'JetBrains Mono', monospace;
  margin-bottom: 0.25rem;
}

/* Colors for specific metrics */
.metric:nth-child(1) .metric-value {
  color: #38bdf8; /* Cyan */
}
.metric:nth-child(2) .metric-value {
  color: #4ade80; /* Green */
}
.metric:nth-child(3) .metric-value {
  color: #facc15; /* Yellow */
}

.metric-label {
  font-size: 12px;
  color: #94a3b8;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ── Features Section ──────────────────────── */
.section-features {
  background: #f0f2f8;
}

.feature-row {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: 3rem;
  align-items: center;
  margin-bottom: 4rem;
}

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

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

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

.feature-number {
  font-size: 4rem;
  font-weight: 900;
  color: rgba(37, 99, 235, 0.08);
  font-family: 'JetBrains Mono', monospace;
  line-height: 1;
  margin-bottom: 0.5rem;
}

.feature-title {
  font-size: 1.8rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.feature-desc {
  font-size: 1rem;
  color: #64748b;
  line-height: 1.7;
  margin-bottom: 1.5rem;
}

.feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.feature-list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.95rem;
  color: #475569;
  line-height: 1.5;
}

.check-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  color: #22c55e;
  margin-top: 2px;
}

.feature-visual {
  position: relative;
}

.feature-visual .screenshot-frame {
  transform: perspective(1200px) rotateY(-3deg);
  transition: transform 0.5s ease;
}

.feature-visual:hover .screenshot-frame {
  transform: perspective(1200px) rotateY(0deg);
}

.feature-row-reverse .feature-visual .screenshot-frame {
  transform: perspective(1200px) rotateY(3deg);
}

.feature-row-reverse .feature-visual:hover .screenshot-frame {
  transform: perspective(1200px) rotateY(0deg);
}

/* ── Architecture Section ──────────────────── */
.section-arch {
  background: #f0f2f8;
}

.arch-flow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  margin-bottom: 3rem;
  flex-wrap: nowrap;
  overflow-x: auto;
  padding: 1.5rem 2rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 20px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.03);
}

.arch-node {
  padding: 1rem 1.25rem;
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  text-align: center;
  min-width: 120px;
  flex-shrink: 0;
  transition: all 0.3s ease;
}

.arch-node:hover {
  background: white;
  border-color: #cbd5e1;
  transform: translateY(-4px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.arch-node-primary {
  border-color: rgba(37, 99, 235, 0.3);
  background: rgba(37, 99, 235, 0.04);
}

.arch-node-accent {
  border-color: rgba(22, 163, 74, 0.3);
  background: rgba(22, 163, 74, 0.04);
}


.arch-node h4 {
  font-size: 0.9rem;
  font-weight: 700;
  color: #0f172a;
  margin-bottom: 0.25rem;
}

.arch-node p {
  font-size: 0.75rem;
  color: #94a3b8;
}

.arch-arrow {
  font-size: 1.5rem;
  color: #cbd5e1;
  font-weight: 300;
}

/* Tech Stack */
.tech-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: #0f172a;
  text-align: center;
  margin-bottom: 1.5rem;
}

.tech-decisions-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.tech-decision-card {
  padding: 1.75rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
  transition: all 0.3s ease;
}

.tech-decision-card:hover {
  border-color: #cbd5e1;
  transform: translateY(-3px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.06);
}

.tech-badge {
  display: inline-block;
  background: rgba(37, 99, 235, 0.08);
  color: #2563eb;
  font-weight: 700;
  font-size: 0.85rem;
  padding: 6px 12px;
  border-radius: 6px;
  margin-bottom: 1.25rem;
}

.tech-decision-card p {
  color: #475569;
  font-size: 0.95rem;
  line-height: 1.6;
}

/* ── Showcase Zig-Zag Section ──────────────── */
.section-showcase {
  background: #f0f2f8;
}

.showcase-block {
  display: grid;
  grid-template-columns: 58% 42%;
  gap: 3rem;
  align-items: center;
  margin-bottom: 5rem;
}

.showcase-block:last-child {
  margin-bottom: 0;
}

.showcase-block-reverse {
  direction: rtl;
}

.showcase-block-reverse > * {
  direction: ltr;
}

.showcase-visual .screenshot-frame {
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
  border-radius: 12px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.showcase-visual .screenshot-frame:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.12);
}

/* Tags */
.showcase-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 4px 10px;
  border-radius: 4px;
  margin-bottom: 1rem;
}

.showcase-tag-red {
  color: #ef4444;
  background: rgba(239, 68, 68, 0.08);
}

.showcase-tag-blue {
  color: #2563eb;
  background: rgba(37, 99, 235, 0.08);
}

.showcase-tag-green {
  color: #16a34a;
  background: rgba(22, 163, 74, 0.08);
}

.showcase-tag-cyan {
  color: #0891b2;
  background: rgba(8, 145, 178, 0.08);
}

.showcase-title {
  font-size: 1.5rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.showcase-desc {
  font-size: 1rem;
  color: #475569;
  line-height: 1.7;
}

.showcase-desc em {
  font-style: italic;
  color: #1e293b;
}

@media (max-width: 1024px) {
  .showcase-block {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .showcase-block-reverse {
    direction: ltr;
  }
}

/* ── Metrics Section ───────────────────────── */
.section-metrics {
  background: #f0f2f8;
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.metric-card {
  padding: 2rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
}

.metric-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #2563eb, #3b82f6);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.metric-card:hover {
  border-color: #cbd5e1;
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.06);
}

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


.metric-card-value {
  font-size: 2.2rem;
  font-weight: 900;
  color: #0f172a;
  font-family: 'JetBrains Mono', monospace;
  letter-spacing: -0.02em;
  margin-bottom: 0.25rem;
}

.metric-card-label {
  font-size: 0.85rem;
  font-weight: 700;
  color: #2563eb;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.75rem;
}

.metric-card-desc {
  font-size: 0.9rem;
  color: #64748b;
  line-height: 1.6;
}

/* ── PM Section ────────────────────────────── */
.section-pm {
  background: #f0f2f8;
}

.pm-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
}

.pm-card {
  padding: 2rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  transition: all 0.3s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
}

.pm-card:hover {
  border-color: #cbd5e1;
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.06);
}

.pm-card-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 1.25rem;
}

.pm-icon {
  font-size: 1.5rem;
}

.pm-card-header h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: #0f172a;
}

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

.pm-list li {
  font-size: 0.9rem;
  color: #64748b;
  padding-left: 1.25rem;
  position: relative;
  line-height: 1.5;
}

.pm-list li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: #2563eb;
  font-weight: 700;
}

/* ── CTA Section ───────────────────────────── */
.section-cta {
  background: #f0f2f8;
  padding: 6rem 0;
}

.cta-content {
  text-align: center;
  max-width: 700px;
  margin: 0 auto;
  padding: 4rem 3rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 24px;
  position: relative;
  overflow: hidden;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.05);
}

.cta-content::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, #2563eb, #3b82f6, #60a5fa);
}

.cta-title {
  font-size: 2.2rem;
  font-weight: 900;
  color: #0f172a;
  margin-bottom: 1rem;
  position: relative;
}

.cta-desc {
  font-size: 1.05rem;
  color: #64748b;
  margin-bottom: 2rem;
  line-height: 1.7;
  position: relative;
}

.cta-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  position: relative;
  flex-wrap: wrap;
}

/* ── Footer — matching retrolab.com.vn ─────── */
.footer {
  padding: 2.5rem 0 1.5rem;
  background: white;
  color: #6b7280; /* text-gray-500 */
  border-top: 1px solid #e5e7eb; /* border-gray-200 */
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2.5rem;
  margin-bottom: 2.5rem;
}

.footer-brand-col .footer-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 800;
  color: #111827; /* text-gray-900 */
  margin-bottom: 1rem;
}

.footer-tagline {
  font-size: 0.875rem;
  color: #6b7280;
  line-height: 1.6;
}

.footer-social {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.75rem;
}

.footer-social a {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: #f0f4ff;
  color: #2563eb;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
}

.footer-social a:hover {
  background: #2563eb;
  color: white;
}

.footer-heading {
  font-size: 1.125rem;
  font-weight: 700;
  color: #111827; /* text-gray-900 */
  margin-bottom: 1.5rem;
}

.footer-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.footer-nav a {
  font-size: 0.875rem;
  color: #6b7280;
  transition: color 0.2s;
}

.footer-nav a:hover {
  color: #2563eb;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 1.5rem;
  border-top: 1px solid #e5e7eb;
  font-size: 0.875rem;
  color: #6b7280;
}

.footer-bottom .heart {
  color: #3b82f6;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }

  .footer-brand-col {
    grid-column: 1 / -1;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
  }
}

/* ── Animations ────────────────────────────── */
@keyframes fade-slide-up {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Scroll-triggered */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Responsive ────────────────────────────── */
@media (max-width: 1024px) {
  .feature-row {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

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

  .feature-visual .screenshot-frame,
  .feature-row-reverse .feature-visual .screenshot-frame {
    transform: none;
  }



  .solution-inner {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .solution-text {
    padding: 3rem 2rem;
  }

  .solution-metrics {
    flex-direction: row;
    justify-content: space-around;
    padding: 3rem 2rem;
  }


  .arch-arrow {
    display: flex;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .hero-stats {
    flex-direction: column;
    gap: 1rem;
    padding: 1.5rem;
  }

  .stat-divider {
    width: 40px;
    height: 1px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .metrics-grid,
  .pm-grid {
    grid-template-columns: 1fr;
  }

  .problems-grid {
    grid-template-columns: 1fr;
  }

  .solution-metrics {
    flex-direction: column;
  }



  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .feature-number {
    font-size: 2.5rem;
  }

  .feature-title {
    font-size: 1.3rem;
  }

  .metric-card-value {
    font-size: 1.8rem;
  }
}