Progressive email-gate checkout, built on WooCommerce — one page, no separate “Log in or Sign up” choice. What renders next depends on whether the email matches an existing account. Runs through this doc as sequential states rather than a live multi-step form.

Claim-code recipients land here from a pre-filtered link via email that pre-loads a single product line into the cart. Same mechanism as an Unlock link, but pointed straight at Checkout. From there it's an ordinary checkout: they add the coupon code themselves to bring the balance to $0.