In the page you referenced, the central element is perhaps the simplest.
Have a wrapping div with a background image and then four equal sized divs inside it.
If you float them they’ll just fall into place. Use percentages instead of px widths and it’ll be responsive too.
In fact, the only thing you will need to ‘position’ is the containing div’s background image.
Something like this: http://codepen.io/anon/pen/FKHoE