My PayPal Checkout button is already embedded in a small JavaScript site, but the flow breaks because I never receive the access token. I have a live client ID and secret in the PayPal dashboard; what I need is the exact code (or quick server snippet) that exchanges those credentials for a valid access token so the button can complete a payment. The project is plain JavaScript—no React, Angular, or other frameworks—so please keep the sample code vanilla. You can use Node, a lightweight PHP file, or even a cURL example if that is faster; I just need something I can drop in, test, and see the token come back successfully in both Sandbox and Live modes. Deliverable: • One clearly-commented code sample that requests and returns the PayPal access token. • A short read-me explaining where to place my credentials and how to trigger the request from the existing button script. • Confirmation it works with the PayPal Checkout flow (createOrder → onApprove). If you’ve handled PayPal Checkout tokens before, this should be quick work—I’m ready to test as soon as you send the files.