Thank you page customization missing?

Why can't I find a place to edit my thank you page? 

I see you have a Card form there. For card forms, Thank You and Welcome page settings are shown at the very top and bottom of form builder. This way, you can find Thank You page below the last card:

Let us know if you need more help. 

Aha! Thank you. The problem is I would like to have a JPEG of a printable gift certificate on the "thank you" page. I don't see a way of doing with the card system. If I have to do a redirect to a separate page, that's ok but I'd prefer to have it here. 

Hello again,

Unfortunately, there are not much options to customize Card forms. But, if this will meet your requirements, you can replace a logo image on Thank You page by clicking on it:

If this will not work good enough for gift certificate, please use a 'redirect to external link' option.