This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
-moz-os-version Gecko-only CSS
@media media feature can be used to apply styles based on the user's version of Microsoft Windows. This can be useful for adapting application skins and other chrome code depending on the user's operating system version.
The user is on the Windows 7 operating system.
The user is on the Windows 8 operating system.
The user is on the Windows 10 operating system.
Accepts min/max prefixes: no