* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    min-width: 400px;
    min-height: 500px;
    font-family: Arial, sans-serif;
    background-color: #f0f8ff;
  }
  
  .wrapper {
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
  }
  
  .container {
    width: 100%;
    max-width: 400px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    background-color: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  }
  
  header {
    text-align: center;
    margin-bottom: 10px;
  }
  
  h1 {
    color: #2c3e50;
    font-size: 28px;
    margin-bottom: 8px;
  }
  
  .subtitle {
    color: #7f8c8d;
    font-size: 14px;
  }
  
  main {
    display: flex;
    flex-direction: column;
    gap: 20px;
  }
  
  .input-group, .output-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
  }
  
  label {
    font-size: 14px;
    color: #2c3e50;
    font-weight: bold;
  }
  
  input {
    width: 100%;
    padding: 12px;
    border: 2px solid #bdc3c7;
    border-radius: 6px;
    font-size: 14px;
    outline: none;
    transition: all 0.3s ease;
  }
  
  input:focus {
    border-color: #4682b4;
    box-shadow: 0 0 0 3px rgba(70, 130, 180, 0.1);
  }
  
  .button-group {
    display: flex;
    gap: 12px;
    justify-content: center;
  }
  
  .primary-btn, .secondary-btn {
    padding: 12px 24px;
    border: none;
    border-radius: 6px;
    font-size: 14px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
  }
  
  .primary-btn {
    background-color: #4682b4;
    color: white;
    width: 100%;
  }
  
  .primary-btn:hover {
    background-color: #5f9ea0;
    transform: translateY(-1px);
  }
  
  .primary-btn:active {
    transform: translateY(0);
  }
  
  .secondary-btn {
    background-color: #95a5a6;
    color: white;
    flex: 1;
  }
  
  .secondary-btn:hover {
    background-color: #7f8c8d;
    transform: translateY(-1px);
  }
  
  .secondary-btn:active {
    transform: translateY(0);
  }
  
  input[readonly] {
    background-color: #f8f9fa;
    cursor: default;
  }
  
  footer {
    margin-top: 20px;
    text-align: center;
    border-top: 1px solid #eee;
    padding-top: 20px;
  }
  
  .copyright {
    font-size: 12px;
    color: #666;
    line-height: 1.5;
  }
  
  .copyright b {
    color: #4682b4;
  }
  
  /* Responsive adjustments */
  @media (max-width: 480px) {
    .container {
      padding: 20px;
    }
  
    h1 {
      font-size: 24px;
    }
  
    .button-group {
      flex-direction: column;
    }
  
    .primary-btn, .secondary-btn {
      width: 100%;
    }
  }