body {
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue",
              "Segoe UI", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  line-height: 1.7;
  margin: 0 auto;
  padding: 16px;
  background-color: #ffffff;
  color: #333333;
  max-width: 1080px;
}

h1 {
  font-size: 1.6em;
  margin-bottom: 0.8em;
  border-bottom: 2px solid #e0e0e0;
  padding-bottom: 0.3em;
  text-align: center;
}

h2 {
  font-size: 1.2em;
  margin-top: 1.8em;
  margin-bottom: 0.6em;
  border-left: 4px solid #4a90e2;
  padding-left: 8px;
}

h3 {
  font-size: 1.05em;
  margin-top: 1.4em;
  margin-bottom: 0.4em;
}

p {
  margin: 0.6em 0;
}

ul {
  margin: 0.6em 0 0.6em 1.2em;
  padding: 0;
}

li {
  margin-bottom: 0.4em;
}

a {
  color: #4a90e2;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}