body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    color: #333;
  }
  
  header {
    background-color: #f4f4f4;
    padding: 1rem;
  }
  
  nav ul {
    list-style-type: none;
    padding: 0;
  }
  
  nav ul li {
    display: inline;
    margin-right: 10px;
  }
  
  .nav-link-index {
    text-decoration: none;
    color: #333;
    font-weight: bold;
    padding: 5px 10px;
    border-radius: 5px;
    transition: background-color 0.3s ease;
  }
  
  .nav-link-index:hover,
  .nav-link-index.active {
    background-color: #ddd;
  }
  
  main {
    padding: 2rem;
    max-width: 800px;
    margin: 0 auto;
  }
  
  h1 {
    color: #2c3e50;
  }
  
  h2 {
    color: #34495e;
    margin-top: 2rem;
  }
  
  footer {
    background-color: #f4f4f4;
    text-align: center;
    padding: 1rem;
    position: fixed;
    bottom: 0;
    width: 100%;
  }