border-width - kann sie Nachkommastellen haben?

[Raketenwilli]

Hm. Quelle?

https://w3c.github.io/csswg-drafts/css-backgrounds/#propdef-border-width

These properties set the thickness of the border. Where

<line-width> = <length [0,∞]> | thin | medium | thick

linkt zu: https://www.w3.org/TR/css-values-4/#length-value

There are two types of length units: relative and absolute. The specified value of a length (specified length) is represented by its quantity and its unit. The computed value of a length (computed length) is the specified length resolved to an absolute length, and its unit is not distinguished: it can be represented by any absolute length unit (but will be serialized using its canonical unit, px).

Das „serialized using its canonical unit“ kann man schon so verstehen, als dürfe der Browser das auf ganze Pixel runden.