:root {
  --primary: #0d9488;
  --primary-dark: #0f766e;
  --primary-light: #ccfbf1;
  --bg: #f8fafc;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --radius: 16px;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

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

body {
  font-family: 'Noto Sans KR', 'Inter', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
}

.hero {
  background: linear-gradient(135deg, #0f766e 0%, #0d9488 100%);
  color: white;
  padding: 80px 0 64px;
  text-align: center;
}

.badge {
  display: inline-block;
  background: rgba(255,255,255,0.15);
  backdrop-filter: blur(4px);
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 18px;
}

.hero h1 {
  font-size: 42px;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 16px;
}

.subtitle {
  font-size: 18px;
  opacity: 0.92;
  margin-bottom: 36px;
  line-height: 1.6;
}

.cta-group {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 26px;
  border-radius: 12px;
  font-weight: 600;
  text-decoration: none;
  font-size: 15px;
  transition: all 0.15s ease;
  border: 2px solid transparent;
}

.btn-primary {
  background: white;
  color: var(--primary-dark);
  box-shadow: var(--shadow);
}

.btn-primary:hover { transform: translateY(-2px); }

.btn-secondary {
  background: transparent;
  color: white;
  border-color: rgba(255,255,255,0.5);
}

.btn-secondary:hover { background: rgba(255,255,255,0.1); }

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 20px;
  margin: -30px auto 48px;
}

.feature-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px 24px;
  text-align: center;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.feature-card .icon {
  font-size: 32px;
  margin-bottom: 14px;
}

.feature-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

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

.guide {
  background: var(--card);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  margin-bottom: 48px;
}

.guide h2 {
  font-size: 22px;
  margin-bottom: 18px;
  margin-top: 32px;
  color: var(--primary-dark);
}

.guide h2:first-child { margin-top: 0; }

.guide ol, .guide ul {
  padding-left: 20px;
  margin-bottom: 18px;
}

.guide li {
  margin-bottom: 12px;
  color: var(--text);
}

.guide code {
  background: #f1f5f9;
  padding: 2px 6px;
  border-radius: 6px;
  font-family: 'Menlo', 'Monaco', monospace;
  font-size: 0.92em;
}

pre {
  background: #0f172a;
  color: #e2e8f0;
  padding: 16px 18px;
  border-radius: 12px;
  overflow-x: auto;
  margin: 12px 0 20px;
}

pre code {
  background: transparent;
  padding: 0;
  color: inherit;
  font-size: 13px;
  line-height: 1.5;
}

kbd {
  background: #e2e8f0;
  border: 1px solid #cbd5e1;
  border-radius: 5px;
  padding: 2px 6px;
  font-size: 0.85em;
  font-family: inherit;
}

.footer {
  text-align: center;
  padding: 28px 0 48px;
  color: var(--muted);
  font-size: 14px;
}

.footer a { color: var(--primary); text-decoration: none; }

@media (max-width: 560px) {
  .hero { padding: 56px 0 48px; }
  .hero h1 { font-size: 32px; }
  .subtitle { font-size: 16px; }
  .guide { padding: 24px; }
  .features { margin-top: -20px; }
}