Hi! Noah is correct, we do not currently have the ability to customize the URL on the landing pages.
We have gotten several requests for this feature, and I checked in with our developers for a status update. It is on the timeline for a future release of Emma sometime early in the fall, so look for this very soon. The expected function of the feature is for you to be able to use your own domain in place of t.e2ma.net in the URL.