:stuck { ... }

The :stuck selector checks if the element is currently “stuck” with the position: sticky.

Explore other not-so-valid CSS things

animation-repeat-period: 3s

display: visually-hidden

display: masonry

:wrapped { ... }

border-color: gradient(...)

collapsing: none

place: center

font-family: system-font

position-items: center

position: temporal

color: anthracite

float: top

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