ok I know how to do both these things separately:
#elemID { } /* selects only one element */
#elemID * { } /* selects all its children elements but not the element itself */
And I know I can do it like this:
#elemID, #elemID * { }
But is there a way to avoid this repeating ?
No, there is nothing shorter than that.
Note that if you really only want all the children of
#elemID, and not all the descendants, you need to use the child combinator:And as Šime Vidas has commented, some properties like
colorare automatically inherited by descendant elements by default. If you’re trying to give text color to#elemID, you should not need to apply it explicitly and recursively to the elements inside it. See the SitePoint Reference on inheritance in CSS for details.