Animated CSS checkboxes to copy

Checkboxes where the check itself is the animation: a tick that draws itself, a circular fill from the centre, an explosion of particles, a task that gets struck through, a box that rotates in 3D, a heart that fills up, a two-stroke tick with bounce, a border that turns into a fill, a colour wave, a neon glow and a padlock that opens.

They keep the native input underneath, so keyboard and screen readers work as usual. Change colour and size, then copy the HTML and CSS into your forms, to-do lists and settings.