Built a four-step checkout with Stripe

Checkout is live on the site. Pick a package, enter your details, pay with Stripe Elements, and land on a full-screen confirmation. Behind the scenes, a webhook fires a confirmation email through Resend and books a 45-minute consultation via Google Calendar automatically. Used PaymentIntents instead of Checkout Sessions so the whole experience stays on-site with no redirects to a third-party page. Handles 3D Secure cleanly — reads the URL params on return and jumps straight to confirmation. Idempotency keys on every intent so duplicate charges cannot happen.