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.
For every action (force applied by one body to a second), there is an equal and opposite reaction (the second applies an equal force on the first but in the opposite direction). Whew! What that means as that your body must absorb the impact forces during high-impact moves.