#aiThumbTool {
  max-width: 800px;
  margin: 40px auto;
  font-family: 'Segoe UI', sans-serif;
}
#aiThumbTool input,
#aiThumbTool select,
#aiThumbTool button {
  width: 100%;
  padding: 12px;
  margin: 10px 0;
  font-size: 16px;
}
#aiThumbTool canvas {
  width: 100%;
  border: 2px dashed #ccc;
  margin-top: 20px;
  border-radius: 12px;
}