body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    margin: 0;
    padding: 0;
  }
  
  .container {
    max-width: 600px;
    margin: 50px auto;
    padding: 20px;
    background: #fff;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  }
  
  h1 {
    text-align: center;
  }
  
  .unit-switcher {
    text-align: center;
    margin-bottom: 20px;
  }
  
  form label {
    display: block;
    margin-top: 10px;
  }
  
  form input, form select {
    width: 100%;
    padding: 10px;
    margin-top: 5px;
  }
  
  button {
    display: block;
    width: 100%;
    padding: 10px;
    margin-top: 20px;
    background-color: #28a745;
    color: #fff;
    border: none;
    cursor: pointer;
  }
  
  button:hover {
    background-color: #218838;
  }
  
  #results {
    margin-top: 30px;
  }