The layers (let’s call it absolute positioned) can be brought into the flow of the page by declaring position in percentage (screencast link below).
The downside:
An absolute positioned item is either the lowest or the highest part of your page-construction (you can’t smuggle them somewhere in between).
In your case the ivy would be the top item (highest z-index) of all items - right?
And there we are:
The current width of this item is 309px. The entire screen of a mobile portrait mode is 320px. So it would cover all and everything, each link and stuff below. This could be re-arranged by simply display:none for all critical device-widths. But hey - not display an important part of the page for one part of the audience? Hm - perhaps it isn’t an important one? Who knows!
*It may sound hard, but responsive means first to change the entire attitude towards web these days. It’s about construction, content, semantic and performance.
The shown example is excellent for a brochure (folder, flyer however you call it) - but not for web 2014. It’s about visual, feel and look (images are not content - just decoration) - things that are secondary or even redundant.