body {
  margin: 0;
  font-family: 'Segoe UI', Roboto, sans-serif;
  background-color: #121212;
  color: #e0e0e0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  min-height: 100vh;
  padding: 20px;
}

header {
  font-size: 2rem;
  margin-bottom: 20px;
  font-weight: bold;
  color: #bb86fc;
}

canvas {
  max-width: 600px;
  max-height: 600px;
  background: #1e1e1e;
  border-radius: 12px;
  padding: 10px;
  box-shadow: 0px 0px 15px rgba(0,0,0,0.5);
}

.error {
  margin-top: 20px;
  color: #ff6b6b;
  font-weight: bold;
}