Can I put a button over an autoplaying gallery?

I'm trying to create a welcome page for a website where it's just images, and then you click a button to get in to get to the actual website. I had it set up with a still image and the button to click in (see photo below) but I'd love to be able to put a similar button over a full-screen gallery. Does anyone have the code to do this? 

Hi,

You can use List Section Banner Slideshow

You can also add 2 sections: Top is Gallery, Under is Section with button, then share site url, we can give code to move Button over Gallery