Apex domains cannot have CNAME records.
Question and response
Question
dig nerv.st. NS
Answer
nerv.st. 5 NS ns1.hopnetworks.net.
nerv.st. 5 NS ns2.hopnetworks.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0