Gleam
background-clip: text plus a moving background position. Four lines, no JS.
Usage
Introducing WunderMotion
Meant for
Examples
On a Badge
A highlight travelling through the letters: background-clip: text plus a moving background-position. Four lines, no character splitting, and it inherits the badge's own label colour through currentColor. It goes on the label inside the badge, because the badge paints its own fill.
The class is wm wm-gleam — the first half is the marker the trigger and reduced-motion rules hook into, the second is the effect.