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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: #f5f7fa;
  color: #333;
  line-height: 1.7;
}

.container {
  max-width: 740px;
  margin: 48px auto;
  padding: 0 24px 64px;
}

header {
  text-align: center;
  margin-bottom: 48px;
}

header h1 {
  font-size: 28px;
  font-weight: 700;
  color: #1a1a1a;
  margin-bottom: 6px;
}

.subtitle {
  font-size: 18px;
  color: #4285f4;
  font-weight: 500;
  margin-bottom: 8px;
}

.updated {
  font-size: 13px;
  color: #999;
}

main {
  background: white;
  border-radius: 12px;
  padding: 40px 48px;
  box-shadow: 0 2px 16px rgba(0, 0, 0, 0.07);
  display: flex;
  flex-direction: column;
  gap: 32px;
}

section h2 {
  font-size: 16px;
  font-weight: 600;
  color: #1a1a1a;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid #e0e4e8;
}

section p {
  font-size: 14px;
  color: #555;
  margin-bottom: 10px;
}

section p:last-child {
  margin-bottom: 0;
}

section ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

section ul li {
  font-size: 14px;
  color: #555;
  padding-left: 20px;
  position: relative;
}

section ul li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: #4285f4;
  font-weight: 700;
}

code {
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 12px;
  background: #f0f4ff;
  color: #4285f4;
  padding: 2px 6px;
  border-radius: 4px;
}

a {
  color: #4285f4;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

footer {
  text-align: center;
  margin-top: 32px;
  font-size: 13px;
  color: #bbb;
}

@media (max-width: 600px) {
  main {
    padding: 28px 24px;
  }

  header h1 {
    font-size: 22px;
  }
}