img.image-sizes {
  max-width: 100%;
}

img.image-sizes.pre-load {
  width: 100%;
  height: auto;
}


img.image-sizes.fade-in-on-load {
  animation-duration: 2s;
  animation-name: fadeInOnLoad;
}

img.image-sizes.pre-load {
  animation: loadingAnimation 2s infinite;
}

@keyframes fadeInOnLoad {
  0% {
    opacity: 0.2;
  }
  100% {
    opacity: 1;
  }
}

@keyframes loadingAnimation {
  0% {
    opacity: 0.8;
  }
  50% {
    opacity: 1;
  }
  100% {
    opacity: 0.8;
  }
}