Looking for help with subdomains. Oliviya (convert kit tutorial) mentions creating a subdomain to point your landing pages to. However, a landing page cannot point to a subdomain directly through convert kit. As an example, I create the subdomain welcome.mydomain.com. I'd like that subdomain to direct to my "Opt in" Landing page I created in convert kit. However, it can only connect IF I use welcome.mydomain.com/opt-in. How can I get it to connect straight to the subdomain.