body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #111;
  color: #eee;
}

.container {
  max-width: 900px;
  margin: auto;
  padding: 20px;
}

.card {
  background: #1b1b1b;
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 20px;
}

button {
  margin: 5px;
  padding: 10px 14px;
  border: none;
  border-radius: 8px;
  background: #2f6fed;
  color: white;
  cursor: pointer;
}

button:hover {
  opacity: 0.9;
}

canvas {
  background: #000;
  border-radius: 12px;
  width: 100%;
  max-width: 400px;
  height: 400px;
}

pre {
  overflow-x: auto;
}