:root {
  --bg: #0D1117;
  --surface: #161B22;
  --border: #30363D;
  --text: #E6EDF3;
  --text-muted: #8B949E;
  --accent: #25D366;
  --accent-dim: rgba(37, 211, 102, 0.15);
  --phone-bg: #1A1F26;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'DM Sans', sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { font-family: 'Space Grotesk', sans-serif; font-weight: 700; }

/* Navigation */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 20px 40px;
  background: rgba(13, 17, 23, 0.8);
  backdrop-filter: blur(12px);
}

.nav-inner { max-width: 1200px; margin: 0 auto; }

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
}

.logo-mark {
  font-size: 24px;
  color: var(--accent);
}

.logo-text {
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 700;
  font-size: 20px;
}

/* Hero */
.hero {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 80px;
  padding: 120px 40px 80px;
  max-width: 1200px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background: var(--accent-dim);
  color: var(--accent);
  border-radius: 100px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.5px;
  margin-bottom: 24px;
}

.hero-headline {
  font-size: clamp(36px, 5vw, 56px);
  line-height: 1.1;
  margin-bottom: 24px;
  background: linear-gradient(135deg, #fff 0%, #8B949E 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: 18px;
  color: var(--text-muted);
  max-width: 480px;
  margin-bottom: 48px;
}

.hero-metrics {
  display: flex;
  align-items: center;
  gap: 24px;
}

.metric {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.metric-value {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 28px;
  font-weight: 700;
}

.metric-value.accent { color: var(--accent); }

.metric-label {
  font-size: 13px;
  color: var(--text-muted);
}

.metric-arrow {
  font-size: 24px;
  color: var(--text-muted);
}

/* Phone Mockup */
.hero-visual {
  display: flex;
  justify-content: flex-end;
}

.phone-mockup {
  width: 300px;
  background: var(--phone-bg);
  border-radius: 24px;
  border: 1px solid var(--border);
  padding: 20px;
  box-shadow: 0 40px 80px rgba(0, 0, 0, 0.4);
}

.phone-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 16px;
}

.contact-avatar {
  width: 40px;
  height: 40px;
  background: var(--accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 18px;
  color: #000;
}

.contact-info { display: flex; flex-direction: column; }
.contact-name { font-weight: 600; font-size: 14px; }
.contact-status { font-size: 12px; color: var(--accent); }

.chat-thread { display: flex; flex-direction: column; gap: 8px; }

.chat-customer, .chat-agent {
  max-width: 85%;
  padding: 10px 14px;
  border-radius: 16px;
  font-size: 13px;
  line-height: 1.4;
}

.chat-customer {
  background: var(--surface);
  align-self: flex-start;
  border-bottom-left-radius: 4px;
}

.chat-agent {
  background: var(--accent-dim);
  color: var(--accent);
  align-self: flex-end;
  border-bottom-right-radius: 4px;
}

.typing-indicator {
  display: flex;
  gap: 4px;
  padding: 10px 14px;
  background: var(--accent-dim);
  border-radius: 16px;
  width: fit-content;
  border-bottom-right-radius: 4px;
}

.typing-indicator span {
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  animation: bounce 1.4s infinite;
}

.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

@keyframes bounce {
  0%, 60%, 100% { transform: translateY(0); }
  30% { transform: translateY(-4px); }
}

/* Features */
.features {
  padding: 100px 40px;
  max-width: 1200px;
  margin: 0 auto;
}

.features-header {
  text-align: center;
  margin-bottom: 64px;
}

.features-header h2 {
  font-size: 36px;
  margin-bottom: 12px;
}

.features-header p {
  color: var(--text-muted);
  font-size: 18px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px;
  transition: all 0.3s ease;
}

.feature-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
}

.feature-icon {
  font-size: 32px;
  color: var(--accent);
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 18px;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.5;
}

/* How */
.how {
  padding: 100px 40px;
  background: var(--surface);
}

.how-content {
  max-width: 700px;
  margin: 0 auto;
  text-align: center;
}

.how-content h2 {
  font-size: 36px;
  margin-bottom: 20px;
}

.how-content > p {
  color: var(--text-muted);
  font-size: 18px;
  margin-bottom: 48px;
}

.how-steps {
  display: flex;
  justify-content: center;
  gap: 48px;
}

.step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.step-num {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  background: var(--accent-dim);
  padding: 8px 16px;
  border-radius: 8px;
}

.step-text {
  font-size: 14px;
  color: var(--text-muted);
}

/* Closing */
.closing {
  padding: 100px 40px;
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
}

.closing h2 {
  font-size: clamp(32px, 4vw, 48px);
  margin-bottom: 20px;
}

.closing p {
  color: var(--text-muted);
  font-size: 20px;
  max-width: 500px;
  margin: 0 auto;
}

/* Footer */
.footer {
  padding: 48px 40px;
  border-top: 1px solid var(--border);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 700;
  font-size: 18px;
}

.footer-tagline {
  color: var(--text-muted);
  font-size: 14px;
}

/* Mobile */
@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
    text-align: center;
    padding-top: 100px;
    gap: 48px;
  }
  
  .hero-content { order: 2; }
  .hero-visual { order: 1; justify-content: center; }
  
  .hero-sub { margin-left: auto; margin-right: auto; }
  .hero-metrics { justify-content: center; }
  
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .how-steps {
    flex-direction: column;
    gap: 32px;
  }
}

@media (max-width: 600px) {
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  .phone-mockup {
    width: 260px;
  }
}