body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    text-align: center;
  }
  header, footer {
    background-color: #333;
    color: #fff;
    padding: 10px;
  }
  nav ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
  }
  nav ul li {
    display: inline;
    margin: 0 10px;
  }
  a {
    color: #fff;
    text-decoration: none;
  }
  a:hover {
    text-decoration: underline;
  }
  .product-card {
    border: 1px solid #ccc;
    padding: 10px;
    margin: 10px;
    display: inline-block;
  }
  .btn {
    display: inline-block;
    background-color: #007bff;
    color: #fff;
    padding: 8px 16px;
    text-decoration: none;
    border-radius: 4px;
    margin: 10px;
  }