Apex domains cannot have CNAME records.
Question and response
Question
dig cross-t.ru. NS
Answer
cross-t.ru. 5 NS ns2.cross-t.ru.
cross-t.ru. 5 NS ns1.cross-t.ru.
Authority
The response has no authority records.
Additional
ns1.cross-t.ru. 5 A 178.212.251.6
ns2.cross-t.ru. 5 A 93.94.152.35
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0