Apex domains cannot have CNAME records.
Question and response
Question
dig static.lyse.net. NS
Answer
static.lyse.net. 5 NS ns2.lyse.net.
static.lyse.net. 5 NS ns1.lyse.net.
Authority
The response has no authority records.
Additional
ns1.lyse.net. 5 A 81.167.36.4
ns2.lyse.net. 5 A 81.167.36.13
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0