#preloader {
  position: fixed;
  inset: 0;
  background: #fff;
  z-index: 99999;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity .6s ease, visibility .6s ease;
}

#preloader.hide {
  opacity: 0;
  visibility: hidden;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid #ddd;
  border-top-color: #000;
  border-radius: 50%;
  animation: spin .8s linear infinite;
}

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