Drawback whereas adjusting my browser-based recreation to resolutions decrease than 1920X1080

I’ve lately developed a web-based 2D poker recreation for desktop setting that runs in net browsers. The sport was constructed utilizing HTML, CSS & JavaScript on consumer aspect, for the optimum display decision of 1920X1080.

The CSS models are “em”s, so with a purpose to proportionally alter every thing to a decrease display decision, all I’ve to do is to alter the bottom font measurement (within the “html” tag) to a decrease worth.
Nevertheless if I accomplish that many issues get distorted, the textual content appears horrible, smudgy and barely readable, some 1 pixel margins disappear, and animations/transitions are affected as nicely (1366X768).
I assume that is in all probability as a consequence of decimal computed css values.

1. Ought to i simply acknowledge that that is how browsers work, or the truth is there’s a approach the sport can nonetheless look good in decrease resolutions similar to 1366X768?
2. Wouldn’t it be superb (in knowledgeable method, not as an opinion) to make additional changes solely to resolutions increased than my optimum 1920X1080?

Thanks upfront.