body {
    font-family: sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #f0f0f0;
  }
  
  input, select, button {
    padding: 10px 15px;
    border: 1px solid #ccc;
    border-radius: 5px;
    margin-bottom: 10px;
    font-size: 16px;
  }
  
  button {
    background-color: #4CAF50;
    color: white;
    cursor: pointer;
  }
  
  #output-value {
    font-size: 20px;
    font-weight: bold;
    margin-top: 10px;
  }