Facebook Fans Capture upon site form submission!

Hi there!
I want to have a nice lightbox pop-up with the offer to join my social media assets (FB, Twitter, YouTube) upon submission of the webform on my website (Carpet Cleaning – https://carpetcleaning1.net). I know there are several plugins like PopUpDominator, but they are pretty hard to theme.

I guess I could’ve served a popup when visitor submits a form and then redirects to a “thank-you” page, where the pop-up could be served. I have seen this strategy implemented on several websites and I thinks everyone would benefit from it.

Thanks in advance!