#preloader {
  position: fixed;
  z-index: 99999;
  width: 100%;
  height: 100%;
  background: #000;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
}

#particles-js {
  position: absolute;
  width: 100%;
  height: 100%;
  z-index: 1;
}