:root {
  --fg: #1e293b;
  --muted: #64748b;
  --bg: #ffffff;
  --surface: #f8fafc;
  --border: #e2e8f0;
  --primary: #3182f6;
  --primary-hover: #2563eb;
  --max-width: 860px;
  --radius: 10px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family:
    -apple-system, BlinkMacSystemFont, "Pretendard", "Noto Sans KR", "Noto Sans JP", "Segoe UI",
    sans-serif;
  color: var(--fg);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}
.site-header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 1rem;
  padding-bottom: 1rem;
  gap: 1rem;
  flex-wrap: wrap;
}
.brand {
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}
.brand strong {
  font-size: 1.25rem;
}
.brand .tagline {
  font-size: 0.85rem;
  color: var(--muted);
}

.lang-switcher {
  display: flex;
  gap: 0.25rem;
  flex-wrap: wrap;
}
.lang-switcher a {
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  text-decoration: none;
  color: var(--muted);
  font-size: 0.875rem;
  border: 1px solid transparent;
}
.lang-switcher a:hover {
  color: var(--fg);
  background: var(--border);
}
.lang-switcher a.active {
  color: var(--primary);
  border-color: var(--primary);
  background: var(--bg);
}

.site-nav {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.site-nav .container {
  display: flex;
  gap: 1.25rem;
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
  flex-wrap: wrap;
}
.site-nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.95rem;
}
.site-nav a:hover {
  color: var(--fg);
}
.site-nav a.active {
  color: var(--primary);
  font-weight: 600;
}

main.content {
  padding-top: 2rem;
  padding-bottom: 4rem;
}

main.content h1 {
  font-size: 1.85rem;
  margin-top: 0.5rem;
}
main.content h2 {
  font-size: 1.35rem;
  margin-top: 2rem;
}
main.content h3 {
  font-size: 1.1rem;
  margin-top: 1.5rem;
}
main.content h4 {
  font-size: 1rem;
}
main.content p {
  margin: 0.75rem 0;
}
main.content ul,
main.content ol {
  padding-left: 1.5rem;
}
main.content li {
  margin: 0.25rem 0;
}
main.content hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

main.content table {
  border-collapse: collapse;
  width: 100%;
  margin: 1rem 0;
}
main.content th,
main.content td {
  border: 1px solid var(--border);
  padding: 0.5rem 0.75rem;
  text-align: left;
  font-size: 0.95rem;
}
main.content th {
  background: var(--surface);
  font-weight: 600;
}

main.content a {
  color: var(--primary);
  text-decoration: none;
}
main.content a:hover {
  text-decoration: underline;
}

main.content strong {
  color: var(--fg);
}

.lead {
  font-size: 1.1rem;
  color: var(--muted);
  margin-bottom: 2rem;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
  margin-top: 1.5rem;
}
.card {
  display: block;
  padding: 1.25rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  color: inherit;
  transition: all 0.15s ease;
  background: var(--bg);
}
.card:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(49, 130, 246, 0.08);
}
.card h2 {
  margin: 0 0 0.25rem;
  font-size: 1.05rem;
  color: var(--fg);
}
.card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  padding: 1.5rem 0;
  margin-top: 3rem;
}
.site-footer p {
  margin: 0;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
}

.root-index {
  background: var(--surface);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}
.root-main {
  text-align: center;
  padding: 3rem 1.25rem;
}
.root-main h1 {
  font-size: 2.25rem;
  margin: 0 0 0.5rem;
}
.lang-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 0.75rem;
  margin-top: 2rem;
  text-align: left;
}
.lang-card {
  display: flex;
  flex-direction: column;
  padding: 1.25rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--fg);
  background: var(--bg);
  transition: all 0.15s ease;
}
.lang-card:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
}
.lang-card strong {
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
}
.lang-card span {
  color: var(--muted);
  font-size: 0.85rem;
}

.root-footer {
  margin-top: 3rem;
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 640px) {
  main.content h1 {
    font-size: 1.5rem;
  }
  main.content h2 {
    font-size: 1.2rem;
  }
  main.content table {
    font-size: 0.85rem;
  }
  main.content th,
  main.content td {
    padding: 0.4rem 0.5rem;
  }
}