#page-container {
  position: relative;
  width: 100%;
}
#page-container::before {
  content: '';
  position: absolute;
  width: 100%;
  height: 100%;
  z-index: 999;
  background: no-repeat url('./page-transition-loading-animation/loading.svg');
  background-size: 100px;
  background-position: center center;
  pointer-events: none;
  opacity: 0;
}
body.page-is-transitioning #page-container::before {
  opacity: 1;
}
#page-content,
#page-container::before {
  transition: opacity 0.5s ease-in-out;
}
body.page-is-transitioning #page-content {
  opacity: 0.17;
}