Wipe

The button and its label track the cursor within a capture radius on separate spring constants, so the label lags the shell and creates depth.

A gooey mass rises from the lower edge on hover, wobbles past level, and settles — the label crossfades to its inverted color as the fill passes.

A bright segment runs the perimeter as a stroke-dash offset, leaving a short fading tail. On hover it accelerates and the fill lifts a step.