$ORIGIN .
$TTL 604800 ; 1 week
example.com    IN SOA  ns01.example.com. root.example.com. (
        33         ; serial
        604800     ; refresh (1 week)
        86400      ; retry (1 day)
        2419200    ; expire (4 weeks)
        604800     ; minimum (1 week)
        )
      NS  ns01.example.com.
      NS  ns02.example.com.
      A 8.8.4.4
      
$ORIGIN example.com.

$TTL 1    ; 1 second
_acme-challenge   IN TXT  w0TwTVFDhq2fUYbuqFiuigIGIGfqiZURWIAR_OUyNyU
_acme-challenge   IN TXT  Ks3zUh7wepiUf2g8GyIGHUkjbGigikqkGHYx7bLMSIA