Apex domains cannot have CNAME records.
Question and response
Question
dig wnd.sh. NS
Answer
wnd.sh. 4 NS ns1.wnd.sh.
wnd.sh. 4 NS ns2.wnd.sh.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0