by clicking and dragging I meant if you click and drag any image (in firefox at least) you can drag around a transparency of that image.. if you drag the white block over the black you you can see faint white lettering.. same with the red one over the white one.. bleh
for those who think these need photoshoppery.. try clicking and dragging the 'ghosts' of the blocks over each other.. voila. No adjustments needed. Way to overcomplicate things.