canisoon

selector list argument of :nth-child and :nth-last-child CSS pseudo-classes

19.29

CSS

The newest versions of `:nth-child()` and `:nth-last-child()` accept an optional `of S` clause which filters the children to only those which match the selector list `S`. For example, `:nth-child(1 of .foo)` selects the first child among the children that have the `foo` class (ignoring any non-`foo` children which precede that child). Similar to `:nth-of-type`, but for arbitrary selectors instead of only type selectors.

Further reading:

  1. Can I use page for: selector list argument of :nth-child and :nth-last-child CSS pseudo-classes
  2. Mozilla Bug 854148 - Support for :nth-child(An+B of sel), :nth-last-child(An+B of sel) pseudo-classes
  3. Chromium Issue 304163: Implement :nth-child(an+b of S) and :nth-last-child(an+b of S) pseudo-classes
  4. MS Edge feature request on UserVoice
  5. MS Edge Platform Status: Under Consideration