--- style.css ---
```css
:root {
  font-size: 16px;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  line-height: 1.5;
  color: #333;
  background-color: #f9f9f9;
}

header {
  background-color: #005fcc;
  color: #fff;
  padding: 1rem;
  text-align: center;
}

.container {
  max-width: 600px;
  margin: 2rem auto;
  padding: 0 1rem;
}

label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: bold;
}

select,
textarea {
  width: 100%;
  padding: 0.5rem;
  border: 1px solid #ccc;
  border-radius: 4px;
  box-sizing: border-box;
}

select {
  margin-bottom: 1rem;
}

textarea {
  resize: vertical;
}

button {
  margin-top: 1rem;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 4px;
  background-color: #005fcc;
  color: #fff;
  font-size: 1rem;
  cursor: pointer;
}

button:disabled {
  background-color: #7da4d9;
  cursor: not-allowed;
}

button:focus-visible {
  outline: 3px solid #ffbf47;
}

#result {
  margin-top: 1.5rem;
  padding: 1rem;
  background-color: #fff;
  border: 1px solid #ddd;
  border-radius: 4px;
}

@media (max-width: 480px) {
  button,
  select,
  textarea {
    width: 100%;
  }
}