body {
  margin: 0;
  padding: 40px;
  background: #f4f4f4;
  font-family: Arial, sans-serif;
}

.container {
  max-width: 700px;
  margin: auto;
  background: white;
  padding: 24px;
  border-radius: 12px;
}

h1 {
  margin-top: 0;
}

.subtitle {
  color: #666;
  margin-bottom: 20px;
}

textarea {
  width: 100%;
  height: 120px;
  padding: 12px;
  box-sizing: border-box;
  font-size: 16px;
  resize: vertical;
}

button {
  margin-top: 16px;
  padding: 12px 18px;
  font-size: 16px;
  cursor: pointer;
}

#output {
  margin-top: 24px;
  white-space: pre-wrap;
  line-height: 1.6;
  background: #fafafa;
  padding: 16px;
  border-radius: 8px;
}