Quote:
Originally Posted by Jellby
Note that :first-letter is not in the required CSS subset of ePUB, so that you cannot rely on any reader supporting it, it's not ADE's fault this time 
Future versions of the spec might include :first-letter and other pseudo elements. |
I'm not sure you're right about that. The ePub spec at
http://www.idpf.org/2007/ops/OPS_2.0_final_spec.html
certainly it says
"The CSS-based style sheet constructs in this specification define required rendering functionality. To minimize the burden on Reading System developers and device manufacturers, not all CSS 2 properties are included. A few additional properties and values have been added to support page layout, headers, and footers. These, taken together, constitute the OPS CSS 2.0 required subset."
and
"A conforming Reading System must render all OPS CSS 2.0 required subset properties."
but I'm not sure that pseudo-elements are a CSS property, which seem to me to be the attributes and values of CSS definitions. Pseudo elements are part of the way that styles are declared, rather than defined.
Indeed, section 3.3 of the above specification is labelled "3.3: Properties", but doesn't have any discussion of how styles are declared, which happens (in part) above in section 3.0.
Further, section 3.1 on Selectors says that reading systems
must support all CSS2 selectors.
Also note that pseudo-elements appear in the CSS2.0 documentation in section 5.12, in the same major section that discusses other selectors, section 5.
http://www.w3.org/TR/1998/REC-CSS2-1.../selector.html
So I think, unless I've missed something obvious, that pseudo-elements are classed as selectors, and are a required part of the ePub specification.