#spinner {
  display: none;
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 1000;
}

.spinner {
  border: 4px solid #f3f3f3;
  border-top: 4px solid #007BFF;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  animation: spin 0.8s linear infinite;
  margin: auto;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}