I'm in the process of putting together a Shopify online store and I've been able to put together a customized popup using HTML, CSS, and JS. I've also incorporated an app in Shopify for email marketing purposes. However, I'm looking to set it up so that when a visitor submits their email through the popup, the app sends them an email. Does anyone have any tips on how to establish a connection between my custom HTML popup and the Shopify app for this purpose?
Thank you