body {
  font-family: 'Segoe UI', sans-serif;
  margin: 40px auto;
  max-width: 900px;
  padding: 0 20px;
  line-height: 1.7;
  background-color: #ffffff;
  color: #333;
}

header {
  text-align: center;
  margin-bottom: 40px;
}

h1 {
  font-size: 32px;
  margin-bottom: 10px;
  color: #004c99;
}

h2 {
  font-size: 24px;
  border-bottom: 2px solid #ddd;
  padding-bottom: 5px;
  margin-top: 40px;
  color: #004c99;
}

h3 {
  font-size: 18px;
  margin-top: 25px;
  color: #333;
}

ul {
  margin-top: 10px;
  padding-left: 20px;
}

li {
  margin-bottom: 8px;
}

.note {
  background-color: #f9f9f9;
  border-left: 4px solid #ff9800;
  padding: 10px 15px;
  margin-top: 15px;
  font-style: italic;
}

footer {
  text-align: center;
  margin-top: 60px;
  font-size: 14px;
  color: #999;
}

.toc {
  background-color: #f0f4f7;
  border: 1px solid #ccc;
  padding: 20px;
  margin-bottom: 30px;
}

.toc h2 {
  margin-top: 0;
}

.toc ul {
  list-style: none;
  padding-left: 0;
}

.toc li {
  margin-bottom: 5px;
}

.toc a {
  color: #004c99;
  text-decoration: none;
}

.toc a:hover {
  text-decoration: underline;
}