body {
    background-image: url('https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSipJRUjdaoRMwY55Gjs_T8s2cxnDbZ9P-F_oKUawZDGmSPmQuHCHFxHsFqLIRlOSzS4nE&usqp=CAU');
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #f4f4f4; /* Light gray background for the entire page */
  }
  
  .courses-container {
    max-width: 1000px;
    padding: 20px;
    border: 2px solid #ccc;
    border-radius: 10px;
    background-color: #ffffff; /* White background for the container */
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1); /* Subtle shadow for the container */
  }
  
  .row {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .class-group {
    margin: 10px;
    border: 2px solid #333;
    border-radius: 10px;
    padding: 10px;
    background-color: #f0f0f0; /* Light gray background for class groups */
  }
  
  .tab {
    overflow: hidden;
    background-color: #e1e1e1; /* Light gray background for tab */
    border-radius: 5px;
    margin-bottom: 10px;
  }
  
  .tab button {
    background-color: #4caf50; /* Green background for tab buttons */
    color: #fff; /* White text color for tab buttons */
    border: none;
    outline: none;
    cursor: pointer;
    padding: 10px 20px;
    transition: background-color 0.3s ease;
    border-radius: 5px;
  }
  
  .tab button:hover {
    background-color: #45a049; /* Darker green color on hover */
  }
  
  .tab button.active {
    background-color: #2980b9; /* Active tab button color */
  }
  
  .class-content {
    display: none;
  }
  
  .course-link {
    display: block;
    margin-bottom: 10px;
    text-decoration: none;
    color: #333;
  }
  
  .course-link:hover {
    text-decoration: underline;
    color: #555; /* Darker color on hover */
  }
  progress-note {
    text-align: center;
    margin-top: 20px;
    color: #888; /* Gray color for the note text */
    font-style: italic;
  }