body {
    background-color: #f8f9fa;
    color: #212529;
  }
  
  body.dark-mode {
    background-color: #121212;
    color: #ffffff;
  }
  
  .card {
    background-color: #ffffff;
  }
  
  .card.dark-mode {
    background-color: #1e1e1e;
    color: #ffffff;
  }
  
  .footer {
    position: fixed;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 30%;
    text-align: center;
    padding: 10px 0;
    background-color: rgba(255, 255, 255, 0.8);
  }
  
  body.dark-mode .footer {
    background-color: rgba(0, 0, 0, 0.8);
  }