/* ==========================================
   Melu Dental LP - Design System
   Color: Navy × Gold × Mint Green
   Matching existing Melu brand identity
   ========================================== */

/* --- CSS Variables --- */
:root {
  --navy: #1B2A4A;
  --navy-light: #2A3D66;
  --navy-dark: #0F1A30;
  --gold: #D4A843;
  --gold-light: #E8C96E;
  --gold-dark: #B8922E;
  --mint: #4ECDC4;
  --mint-light: #7EDDD7;
  --mint-dark: #3AADA5;
  --white: #FFFFFF;
  --off-white: #F9FAFB;
  --light-gray: #F0F2F5;
  --gray: #6B7280;
  --dark: #111827;
  --highlight: rgba(255, 237, 160, 0.5);
  --shadow: 0 4px 20px rgba(27, 42, 74, 0.08);
  --shadow-lg: 0 8px 40px rgba(27, 42, 74, 0.12);
  --radius: 12px;
  --radius-lg: 20px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Noto Sans JP', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--dark);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

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

/* --- Layout --- */
.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

.container-narrow {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
}

.section-white { background: var(--white); }
.section-light { background: var(--off-white); }
.section-pale { background: var(--light-gray); }
.section-navy { background: var(--navy); }

.section-gradient {
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-light) 100%);
}

/* --- Section Labels & Titles --- */
.section-label {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--mint);
  text-align: center;
  margin-bottom: 12px;
}

.section-label-light {
  color: var(--gold);
}

.section-title {
  font-size: 2rem;
  font-weight: 900;
  text-align: center;
  line-height: 1.5;
  margin-bottom: 20px;
  color: var(--navy);
}

.section-title-light {
  color: var(--white);
}

.section-subtitle {
  font-size: 1rem;
  color: var(--gray);
  text-align: center;
  max-width: 640px;
  margin: 0 auto 48px;
  line-height: 1.8;
}

.highlight-marker {
  background: linear-gradient(transparent 60%, var(--highlight) 60%);
  padding: 0 4px;
  font-weight: 700;
}

.highlight-gold {
  color: var(--gold);
  font-weight: 700;
}

/* --- Header --- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: var(--transition);
  background: transparent;
}

.header.scrolled {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
  padding: 10px 0;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: baseline;
  gap: 6px;
}

.logo-sub {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--white);
  transition: var(--transition);
}

.header.scrolled .logo-sub {
  color: var(--navy);
}

.logo-main {
  font-size: 1.5rem;
  font-weight: 900;
  color: var(--gold);
  letter-spacing: 0.05em;
}

.nav {
  display: flex;
  gap: 28px;
}

.nav a {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--white);
  transition: var(--transition);
  position: relative;
}

.header.scrolled .nav a {
  color: var(--navy);
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gold);
  transition: var(--transition);
}

.nav a:hover::after {
  width: 100%;
}

.header-cta {
  display: inline-block;
  padding: 8px 20px;
  background: var(--mint);
  color: var(--white) !important;
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 700;
  transition: var(--transition);
}

.header-cta:hover {
  background: var(--mint-dark);
  transform: translateY(-2px);
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--white);
  transition: var(--transition);
}

.header.scrolled .hamburger span {
  background: var(--navy);
}

/* --- Hero --- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(27, 42, 74, 0.75) 0%,
    rgba(27, 42, 74, 0.45) 50%,
    rgba(27, 42, 74, 0.3) 100%
  );
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 120px 24px 60px;
  max-width: 900px;
}

.hero-badge {
  display: inline-block;
  padding: 8px 24px;
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 100px;
  color: var(--white);
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 2.8rem;
  font-weight: 900;
  color: var(--white);
  line-height: 1.4;
  margin-bottom: 20px;
}

.hero-title-accent {
  color: var(--gold);
  font-size: 3.2rem;
}

.hero-title .highlight-marker {
  background: linear-gradient(transparent 60%, rgba(212, 168, 67, 0.4) 60%);
}

.hero-sub {
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.9);
  line-height: 1.8;
  margin-bottom: 36px;
}

.hero-boxes {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 40px;
}

.hero-box {
  padding: 18px 32px;
  border-radius: var(--radius);
  text-align: center;
  min-width: 180px;
}

.hero-box-light {
  background: rgba(255, 255, 255, 0.9);
  border: 2px solid rgba(255, 255, 255, 0.3);
}

.hero-box-dark {
  background: var(--navy);
  border: 2px solid var(--gold);
}

.hero-box-label {
  display: block;
  font-size: 1.1rem;
  font-weight: 700;
}

.hero-box-light .hero-box-label { color: var(--navy); }
.hero-box-dark .hero-box-label { color: var(--white); }

.hero-box-sub {
  display: block;
  font-size: 0.75rem;
  margin-top: 4px;
}

.hero-box-light .hero-box-sub { color: var(--gray); }
.hero-box-dark .hero-box-sub { color: var(--gold); }

.hero-plus {
  font-size: 1.5rem;
  font-weight: 300;
  color: rgba(255, 255, 255, 0.8);
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 24px;
}

.stat-circle {
  width: 130px;
  height: 130px;
  border-radius: 50%;
  background: var(--gold);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 30px rgba(212, 168, 67, 0.3);
}

.stat-number {
  font-size: 2rem;
  font-weight: 900;
  color: var(--white);
  line-height: 1;
}

.stat-number small {
  font-size: 1rem;
  font-weight: 700;
}

.stat-label {
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--white);
  margin-top: 4px;
}

.stat-award .stat-number-small {
  font-size: 0.9rem;
  font-weight: 900;
  color: var(--white);
}

.stat-award .stat-label-bold {
  font-size: 0.65rem;
  font-weight: 900;
  color: var(--white);
  line-height: 1.3;
  text-align: center;
}

/* --- Problem Section --- */
.problem-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin-top: 48px;
}

.problem-card {
  background: var(--white);
  border: 1px solid var(--light-gray);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
  opacity: 0;
  transform: translateY(30px);
}

.problem-card.animate-in {
  opacity: 1;
  transform: translateY(0);
}

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

.problem-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 20px;
}

.problem-icon svg {
  width: 100%;
  height: 100%;
}

.problem-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 12px;
}

.problem-desc {
  font-size: 0.9rem;
  color: var(--gray);
  line-height: 1.8;
}

.problem-extra {
  margin-top: 28px;
  display: flex;
  justify-content: center;
}

.problem-extra-card {
  background: linear-gradient(135deg, #fff8e1 0%, #fff 100%);
  border: 1px solid rgba(212, 168, 67, 0.2);
  border-radius: var(--radius-lg);
  padding: 28px 40px;
  display: flex;
  align-items: center;
  gap: 24px;
  max-width: 600px;
  box-shadow: var(--shadow);
}

.problem-extra-icon {
  width: 60px;
  height: 60px;
  flex-shrink: 0;
}

.problem-extra-icon svg {
  width: 100%;
  height: 100%;
}

.problem-extra-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 8px;
}

.problem-extra-desc {
  font-size: 0.85rem;
  color: var(--gray);
  line-height: 1.7;
}

.problem-footer {
  text-align: center;
  margin-top: 40px;
  font-size: 1rem;
  color: var(--navy);
  font-weight: 500;
}

/* --- Cause Section --- */
.cause-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-top: 48px;
}

.cause-item {
  display: flex;
  gap: 20px;
  margin-bottom: 32px;
  opacity: 0;
  transform: translateX(-30px);
}

.cause-item.animate-in {
  opacity: 1;
  transform: translateX(0);
}

.cause-number {
  font-size: 2rem;
  font-weight: 900;
  color: var(--gold);
  line-height: 1;
  flex-shrink: 0;
  opacity: 0.7;
}

.cause-item-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 8px;
}

.cause-item-desc {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.8;
}

.cause-visual {
  text-align: center;
}

.cause-image {
  border-radius: var(--radius-lg);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
  margin-bottom: 16px;
}

.cause-caption {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.8);
}

/* --- Solution Section --- */
.solution-cards {
  display: flex;
  flex-direction: column;
  gap: 48px;
  margin-top: 48px;
}

.solution-card {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  position: relative;
  opacity: 0;
  transform: translateY(30px);
}

.solution-card.animate-in {
  opacity: 1;
  transform: translateY(0);
}

.solution-card:nth-child(even) {
  direction: rtl;
}

.solution-card:nth-child(even) > * {
  direction: ltr;
}

.solution-card-number {
  position: absolute;
  top: 20px;
  left: 20px;
  font-size: 4rem;
  font-weight: 900;
  color: var(--gold);
  opacity: 0.15;
  z-index: 2;
  line-height: 1;
}

.solution-card:nth-child(even) .solution-card-number {
  left: auto;
  right: 20px;
}

.solution-card-image {
  position: relative;
  overflow: hidden;
}

.solution-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  min-height: 320px;
  transition: transform 0.6s ease;
}

.solution-card:hover .solution-card-image img {
  transform: scale(1.05);
}

.solution-card-body {
  padding: 48px 40px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.solution-card-title {
  font-size: 1.5rem;
  font-weight: 900;
  color: var(--navy);
  margin-bottom: 4px;
}

.solution-card-subtitle {
  font-size: 0.8rem;
  color: var(--gold);
  font-weight: 500;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.solution-card-desc {
  font-size: 0.95rem;
  color: var(--gray);
  line-height: 1.8;
  margin-bottom: 20px;
}

.solution-card-list {
  list-style: none;
}

.solution-card-list li {
  padding: 6px 0;
  font-size: 0.9rem;
  color: var(--navy);
  font-weight: 500;
  position: relative;
  padding-left: 24px;
}

.solution-card-list li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--mint);
  font-weight: 700;
}

/* --- AI Section --- */
.ai-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 48px;
}

.ai-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
  opacity: 0;
  transform: translateY(20px);
}

.ai-card.animate-in {
  opacity: 1;
  transform: translateY(0);
}

.ai-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.ai-card-icon {
  font-size: 2rem;
  margin-bottom: 12px;
}

.ai-card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 8px;
}

.ai-card-desc {
  font-size: 0.8rem;
  color: var(--gray);
  line-height: 1.7;
}

.ai-cta-box {
  margin-top: 48px;
  text-align: center;
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-light) 100%);
  border-radius: var(--radius-lg);
  padding: 40px;
}

.ai-cta-text {
  font-size: 1.1rem;
  color: var(--white);
  font-weight: 500;
  margin-bottom: 20px;
}

/* --- Merit Section --- */
.merit-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 48px;
}

.merit-grid .merit-card:nth-child(4),
.merit-grid .merit-card:nth-child(5) {
  grid-column: span 1;
}

.merit-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  opacity: 0;
  transform: translateY(20px);
}

.merit-card.animate-in {
  opacity: 1;
  transform: translateY(0);
}

.merit-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.merit-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--gold) 0%, var(--mint) 100%);
}

.merit-number {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--gold);
  opacity: 0.2;
  position: absolute;
  top: 16px;
  right: 24px;
  line-height: 1;
}

.merit-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 12px;
}

.merit-desc {
  font-size: 0.9rem;
  color: var(--gray);
  line-height: 1.8;
}

/* --- Revenue Section --- */
.revenue-desc {
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.85);
  text-align: center;
  margin-bottom: 32px;
}

.revenue-note {
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.6);
  text-align: center;
  margin-top: 16px;
}

/* --- Flow Section --- */
.flow-steps {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 0;
  margin-top: 48px;
}

.flow-step {
  text-align: center;
  max-width: 220px;
  flex: 1;
  opacity: 0;
  transform: translateY(20px);
}

.flow-step.animate-in {
  opacity: 1;
  transform: translateY(0);
}

.flow-step-number {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  color: var(--mint);
  margin-bottom: 12px;
}

.flow-step-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.flow-step-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 8px;
}

.flow-step-desc {
  font-size: 0.85rem;
  color: var(--gray);
  line-height: 1.7;
}

.flow-connector {
  width: 60px;
  height: 2px;
  background: linear-gradient(90deg, var(--mint) 0%, var(--gold) 100%);
  margin-top: 60px;
  flex-shrink: 0;
}

/* --- Q&A Section --- */
.qa-list {
  max-width: 720px;
  margin: 48px auto 0;
}

.qa-item {
  border: 1px solid var(--light-gray);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
  background: var(--white);
  transition: var(--transition);
}

.qa-item:hover {
  box-shadow: var(--shadow);
}

.qa-question {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 24px;
  background: none;
  border: none;
  cursor: pointer;
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--navy);
  text-align: left;
}

.qa-question span:first-child {
  width: 28px;
  height: 28px;
  background: var(--gold);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  flex-shrink: 0;
}

.qa-question span:nth-child(2) {
  flex: 1;
}

.qa-toggle {
  font-size: 1.5rem;
  color: var(--gold);
  transition: var(--transition);
  flex-shrink: 0;
}

.qa-item.active .qa-toggle {
  transform: rotate(45deg);
}

.qa-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.qa-item.active .qa-answer {
  max-height: 200px;
}

.qa-answer p {
  padding: 0 24px 20px 68px;
  font-size: 0.9rem;
  color: var(--gray);
  line-height: 1.8;
}

/* --- CTA Section --- */
.section-cta {
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-dark) 100%);
  text-align: center;
}

.cta-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--white);
  line-height: 1.8;
  margin-bottom: 32px;
}

.cta-note {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.7);
  margin-top: 24px;
  line-height: 1.8;
}

/* --- Buttons --- */
.btn {
  display: inline-block;
  padding: 14px 32px;
  border-radius: 100px;
  font-family: inherit;
  font-weight: 700;
  font-size: 1rem;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  text-align: center;
}

.btn-primary {
  background: var(--mint);
  color: var(--white);
}

.btn-primary:hover {
  background: var(--mint-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(78, 205, 196, 0.4);
}

.btn-gold {
  background: var(--gold);
  color: var(--white);
}

.btn-gold:hover {
  background: var(--gold-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(212, 168, 67, 0.4);
}

.btn-mint {
  background: var(--mint);
  color: var(--white);
}

.btn-mint:hover {
  background: var(--mint-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(78, 205, 196, 0.4);
}

.btn-lg {
  padding: 18px 48px;
  font-size: 1.1rem;
}

.btn-xl {
  padding: 20px 56px;
  font-size: 1.2rem;
  letter-spacing: 0.02em;
}

/* --- Footer --- */
.footer {
  background: var(--navy-dark);
  padding: 48px 0 32px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 32px;
}

.footer-brand .logo-sub {
  color: rgba(255, 255, 255, 0.7);
}

.footer-info p {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
  margin-bottom: 4px;
}

.footer-copy {
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.4);
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* --- Animations --- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.problem-card, .solution-card, .merit-card, .flow-step, .ai-card, .cause-item {
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.problem-card:nth-child(2), .ai-card:nth-child(2), .merit-card:nth-child(2) { transition-delay: 0.1s; }
.problem-card:nth-child(3), .ai-card:nth-child(3), .merit-card:nth-child(3) { transition-delay: 0.2s; }
.ai-card:nth-child(4), .merit-card:nth-child(4) { transition-delay: 0.3s; }
.merit-card:nth-child(5) { transition-delay: 0.4s; }

.solution-card:nth-child(2) { transition-delay: 0.15s; }
.solution-card:nth-child(3) { transition-delay: 0.3s; }

.flow-step:nth-child(3) { transition-delay: 0.1s; }
.flow-step:nth-child(5) { transition-delay: 0.2s; }
.flow-step:nth-child(7) { transition-delay: 0.3s; }

.cause-item:nth-child(2) { transition-delay: 0.15s; }
.cause-item:nth-child(3) { transition-delay: 0.3s; }

/* --- Responsive --- */
@media (max-width: 1024px) {
  .hero-title { font-size: 2.2rem; }
  .hero-title-accent { font-size: 2.6rem; }
  .solution-card { grid-template-columns: 1fr; }
  .solution-card:nth-child(even) { direction: ltr; }
  .solution-card-image img { min-height: 240px; }
  .cause-content { grid-template-columns: 1fr; gap: 40px; }
  .merit-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .section { padding: 64px 0; }

  .nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(27, 42, 74, 0.98);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 32px;
    z-index: 998;
  }

  .nav.active {
    display: flex;
  }

  .nav a {
    font-size: 1.2rem;
    color: var(--white) !important;
  }

  .header-cta { display: none; }
  
  .hamburger {
    display: flex;
    z-index: 999;
  }

  .hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }
  .hamburger.active span:nth-child(2) {
    opacity: 0;
  }
  .hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .hero { min-height: 100svh; }
  .hero-title { font-size: 1.7rem; }
  .hero-title-accent { font-size: 2rem; }
  .hero-sub { font-size: 0.9rem; }

  .hero-boxes { flex-direction: column; gap: 12px; }
  .hero-box { min-width: 200px; padding: 14px 28px; }
  .hero-plus { transform: rotate(90deg); }

  .hero-stats { gap: 12px; }
  .stat-circle { width: 100px; height: 100px; }
  .stat-number { font-size: 1.5rem; }
  .stat-number small { font-size: 0.75rem; }

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

  .problem-grid { grid-template-columns: 1fr; gap: 20px; }
  .problem-extra-card { flex-direction: column; text-align: center; }

  .solution-card-body { padding: 28px 24px; }
  .solution-card-title { font-size: 1.2rem; }

  .ai-grid { grid-template-columns: repeat(2, 1fr); }
  .merit-grid { grid-template-columns: 1fr; }

  .flow-steps { flex-direction: column; align-items: center; gap: 0; }
  .flow-connector { width: 2px; height: 32px; margin: 0; }

  .cta-title { font-size: 1.2rem; }
  .btn-xl { padding: 16px 40px; font-size: 1rem; }

  .footer-inner { flex-direction: column; gap: 24px; }
}

@media (max-width: 480px) {
  .hero-title { font-size: 1.4rem; }
  .hero-title-accent { font-size: 1.6rem; }
  .hero-stats { flex-wrap: wrap; justify-content: center; }
  .ai-grid { grid-template-columns: 1fr; }
}