.preloader {
  position: fixed;
  left: 0;
  top: 50px;
  right: 0;
  bottom: 55px;
  overflow: hidden;
  background: rgba(255,255,255,0.5);
  z-index: 9;
}

.preloader__image {
  position: relative;
  top: 50%;
  left: 50%;
  width: 100px;
  height: 100px;
  margin-top: -32px;
  margin-left: -32px;
  background: url('/assets/img/logo_empty7.gif') no-repeat 100% 100%;
  /*расположение (url) изображения gif и др. параметры*/
}

.loaded_hiding .preloader {
  transition: 1s opacity;
  opacity: 0;
}

.loaded .preloader {
  display: none;
}

.downloaded_hinding .preloader {
  transition: 1s opacity;
  opacity: 1;
}