It shouldn't matter what the sizes are, only the size relative to other element matters when it comes to the design. The unit might as well be 1d (for distance

It shouldn't matter what the sizes are, only the size relative to other element matters when it comes to the design. The unit might as well be 1d (for distance) because the browser can scale the representation of the scenegraph up and down like any vector graphics viewers, think PDF. It's also a small task to offer an alternative CSS for those who want to read the text instead of admiring the spaciousness of the design and the tininess of the fonts.