[css3-selectors] scar cosmetic

- 7. Pseudo-elements
   "For compatibility with existing style sheets, user agents must also
   accept the previous one-colon notation for pseudo-elements introduced in
   CSS levels 1 and 2 (namely, :first-line, :first-letter, :before and
   :after). This compatibility is not allowed for the new pseudo-elements
   introduced in this specification"

   at least "in this specification" nonsence.

- 12. Profiles / CSS level 1 | 2 / Excludes
   "all UI element fragments pseudo-elements"

   what's this?