How do I get at the values in the element?

I'm just a bit confused as to how I get the values entered in the `stripe-card` element. I don't want to use the block form because I have a submit button outside of this element that will send along some other data to a server endpoint that creates a paysource in the customers stripe account. Can I have the values bound to some sort of controller / component property so I can get at those later when the user hits the submit button I have outside of the element?

The issue does not name any files, tests, or entry points. Start by tracing how the `stripe-card` element exposes values and how its block form submits them; determine whether an external submit flow is supported and document or test the expected integration once the behavior is defined.

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