Question

Instead of absolutely positioning (I have to do that, don’t ask why) elements over other elements by searching through, finding the parent elements and then prepending to them, is it possible to find the locations of certain elements by coordinates and then simply recalculate coordinates of the replacements when the window is resized?

Answer 1

You can do this by subtracting your margins.

If you were to append a child into a container that already contained a child just subtract the same height as the existing child from the new childs margin.

Notice the margin-top:-100px below

  <div id="parentContainer" style="width:100px;height:100px;float:left">

        <div id="child1" style="width:100px;height:100px;float:left;background-color:red">

        </div>

        <div id="child2" style="width:100px;height:100px;float:left;background-color:blue;
                                margin-top:-100px">
        </div>

  </div>

If you prepend the do a margin-bottom:-100px