Apex domains cannot have CNAME records.
Question and response
Question
dig webflow.com. NS
Answer
webflow.com. 5 NS ns-958.awsdns-55.net.
webflow.com. 5 NS ns-344.awsdns-43.com.
webflow.com. 5 NS ns-1722.awsdns-23.co.uk.
webflow.com. 5 NS ns-1078.awsdns-06.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0