body {
  font-family: Arial, sans-serif;
  line-height: 1.6;
  margin: 0;
  padding: 0;
  background-color: #f4f4f4;
  color: #333;
}
.container {
  max-width: 800px;
  margin: 20px auto;
  padding: 20px;
  background: #fff;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}
h1, h2 {
  color: #2c3e50;
}
h1 {
  text-align: center;
  margin-bottom: 20px;
}
h2 {
  margin-top: 20px;
}
p {
  margin: 10px 0;
}
ul {
  margin: 10px 0;
  padding-left: 20px;
}
a {
  color: #3498db;
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}
.toggle-section {
  cursor: pointer;
  background: #3498db;
  color: #fff;
  padding: 10px;
  border-radius: 4px;
  margin: 10px 0;
  transition: background 0.3s;
}
.toggle-section:hover {
  background: #2980b9;
}
.section-content {
  display: none;
  padding: 10px;
  border-left: 2px solid #3498db;
  margin-left: 10px;
}
.section-content.active {
  display: block;
}
footer {
  text-align: center;
  padding: 20px;
  background: #2c3e50;
  color: #fff;
  margin-top: 20px;
}
.main-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background-color: #2c3e50;
  padding: 10px 20px;
  color: white;
  position: sticky;
  top: 0;
  z-index: 1000;
  flex-wrap: wrap;
}
.main-header .logo {
  font-size: 20px;
  font-weight: bold;
}
.navbar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.navbar a {
  color: white;
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 4px;
  transition: background 0.3s;
}
.navbar a:hover {
  background-color: #1a252f;
}
.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: white;
  font-size: 24px;
  cursor: pointer;
}
@media (max-width: 768px) {
  .navbar {
    display: none;
    flex-direction: column;
    width: 100%;
    background-color: #2c3e50;
    margin-top: 10px;
  }
  .navbar.active {
    display: flex;
  }
  .menu-toggle {
    display: block;
  }
}