Apex domains cannot have CNAME records.
Question and response
Question
dig static.fibianet.dk. NS
Answer
static.fibianet.dk. 5 NS ns2.fibianet.dk.
static.fibianet.dk. 5 NS ns1.fibianet.dk.
Authority
The response has no authority records.
Additional
ns1.fibianet.dk. 5 A 80.71.80.77
ns2.fibianet.dk. 5 A 80.71.80.78
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0