>>84148
Woah, awesome.
Fixed aspect ratio is usually something like

img {
width: auto;
height: auto;
max-width: 100%;
max-height: 100%;
}

The child element has its width and height set to the size of the image. Setting max-width and max-height, along with auto for width and height, seems to do the trick.
Although that gives dynamic scaling when moving the cursor