I cant get the MX records set on a squarespace domain

I cant get the MX records set on a squarespace domain

MX Records
Subdomain Priority Hostname  
.jds-constructionco.com
This is what it looks like.  It doesn't have the option to just add a domain.  

Here is the error.
DNS Zone could not be set for jds-constructionco.com. (Destination host must be set to a valid hostname, or IP address only for subdomain "mx.zohomail.com")

It also will not accept a blank or @ in the hostname field.