@include all-but-first-last($num) {} // applies style all except first and last child
@include unique {} // applies style to a child who has no siblings
@include not-unique {} // applies style to all children except a child who has no siblings
-@include between($first, $last) {}
+@include between($first, $last) {} // applies style to all except first and last child
@include even {} // applies style to all even children
@include even-between($first, $last) {} // applies style to all even children except first and last
@include odd {} // applies style to all odd children