Precisely fit a background frame behind a GIF

I have a nicely animated GIF of a screen showing a demo of an iPhone app. I’d like to be able to add a frame around the GIF to make it look like a mobile iPhone. Here’s an example of what I’d like to achieve: http://lifetales.com (slide down to page 2)

I also need it to be responsive, and work on all size screens, so the frame needs to be tightly locked in size to the GIF. I tried doing this using backgrounds in several stacks but I’m clearly flailing (and failing)

Any suggestions? I’m currently using Joe Workman’s Foundation theme. Thanks for your help!

Never mind. The terrific ninja at joeworkman.net (Robert Ziebol) showed me how to do it using the Target stack. Easy as pie!

Thanks for the kind words @harvey, glad we worked it out!!
:smile: