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