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