:root {
  --bg: #ffffff;
  --border: #d4d4d4;
  --secondary: #b3b3b3;
  --dark: #2b2b2b;
}

body {
  background-color: var(--bg);
  color: var(--dark);
  font-family: -apple-system, BlinkMacSystemFont, "Inter", sans-serif;
  display: flex;
  justify-content: center;
  padding: 40px 20px;
  margin: 0;
}

.container {
  width: 100%;
  max-width: 650px;
}

header {
  margin-bottom: 40px;
}

h1 {
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

textarea {
  width: 100%;
  padding: 15px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 1rem;
  resize: none;
  outline: none;
  transition: border-color 0.2s;
}

textarea:focus {
  border-color: var(--dark);
}

button {
  background-color: var(--dark);
  color: #ffffff;
  border: none;
  padding: 12px 24px;
  border-radius: 6px;
  font-weight: 500;
  cursor: pointer;
  margin-top: 10px;
  transition: opacity 0.2s;
}

button:hover {
  opacity: 0.9;
}

button:disabled {
  background-color: var(--secondary);
  cursor: not-allowed;
}

#output {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  line-height: 1.6;
  white-space: pre-wrap;
}

.loading {
  color: var(--secondary);
  font-style: italic;
}