body {
    font-family: Arial, sans-serif;
    background-color: #f2f2f2;
    margin: 0;
    padding: 20px;
  }
  
  h1 {
    text-align: center;
  }
  
  .container {
    max-width: 400px;
    margin: 0 auto;
    background-color: #fff;
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  }
  
  label {
    display: block;
    margin-bottom: 10px;
  }
  
  input[type="number"],
  select {
    width: 100%;
    padding: 8px;
    border-radius: 3px;
    border: 1px solid #ccc;
    box-sizing: border-box;
  }
  
  button {
    display: block;
    width: 100%;
    padding: 10px;
    margin-top: 10px;
    background-color: #4CAF50;
    color: #fff;
    border: none;
    border-radius: 3px;
    cursor: pointer;
  }
  
  button:hover {
    background-color: #45a049;
  }
  
  .result {
    margin-top: 20px;
    text-align: center;
  }
  
  h2, h1 {
    margin: 0;
  }
  
  h2 {
    margin-bottom: 10px;
  }
  
  h1 {
    font-size: 48px;
    color: #4CAF50;
  }