This is a little reminder that there is a CSS property for helping control what happens to images as they scale up: image-rendering.
We're quite used to the idea that scaling an image larger than its natural size (upscaling) causes it to be blurry. As awful as that is, it's the browser doing the best it can to algorithmically smooth out an image over more pixels than it has data. But let's say you'd really rather not it do that. Say the image is already pixel-y (pixel art), or you prefer the look of a pixelated upscaling.
You can do it!