So you can tweak the positional difference between the placeholder text and value simply by tweaking the padding or line-height using that pseudo-element selector: input[type=text] { padding:4px; } input[type=text]::-webkit-input-placeholder { padding-top:5px; } Or whatever.
Identifying and describing action-reaction force pairs is a simple matter of identifying the two interacting objects and making two statements describing who is pushing on whom and in what direction. For example, consider the interaction between a baseball bat and a baseball.
Ted Williams once said the most difficult thing in sports is hitting a baseball. Tennis players wield racquets, not bats, but they must return 120 mph serves and hit hundreds of fastballs, change-ups, and slices for hours while constantly in motion, not dug in and awaiting a pitch delivered to their strike zone.