:root {
  --color-bg: #ffffff;
  --color-surface: #f8f9fa;
  --color-border: #e1e4e8;
  --color-text: #24292e;
  --color-text-secondary: #586069;
  --color-accent: #2f81f7;
  --color-accent-hover: #1a6fe0;
  --color-disabled: #b0b8c1;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

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

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
}

header {
  padding: 64px 0 32px;
  text-align: center;
}

header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  font-family: var(--font-mono);
}

.version-badge {
  font-size: 1rem;
  font-weight: 400;
  padding: 2px 10px;
  border-radius: 12px;
  background: var(--color-surface);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  vertical-align: middle;
}

header p {
  margin-top: 16px;
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  max-width: 540px;
  margin-left: auto;
  margin-right: auto;
}

.docs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin: 48px 0;
}

.doc-card {
  display: block;
  padding: 24px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  text-decoration: none;
  color: var(--color-text);
  transition: border-color 0.15s, box-shadow 0.15s;
}

.doc-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 2px 8px rgba(47, 129, 247, 0.1);
}

.doc-card.disabled {
  opacity: 0.5;
  pointer-events: none;
}

.doc-card h2 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.doc-card p {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

.doc-card .badge {
  display: inline-block;
  font-size: 0.75rem;
  padding: 2px 8px;
  border-radius: 12px;
  background: var(--color-surface);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  margin-top: 12px;
}

footer {
  margin-top: auto;
  padding: 32px 0;
  text-align: center;
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  border-top: 1px solid var(--color-border);
}

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

footer a:hover {
  text-decoration: underline;
}

@media (max-width: 480px) {
  header {
    padding: 40px 0 24px;
  }

  header h1 {
    font-size: 2rem;
  }

  .docs-grid {
    grid-template-columns: 1fr;
    margin: 32px 0;
  }
}