#preloader {
  position: fixed;
  top: 0; left: 0; width: 100%; height: 100%;
  background-color: #ffffff;
  display: flex; justify-content: center; align-items: center;
  z-index: 9999;
  transition: opacity 0.5s ease;
}
/* Простая анимация крутилки */
.spinner {
  width: 50px; height: 50px;
  border: 5px solid #ededed;
  border-top: 5px solid #0056b3;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}
@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}
.loader-hidden {
  opacity: 0;
  pointer-events: none;
}