https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors/:valid
:valid CSS pseudo-class - CSS | MDN
valid csspseudoclassmdn
https://css-tricks.com/almanac/pseudo-selectors/v/valid/
:valid | CSS-Tricks
valid csstricks
https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors/:user-valid
:user-valid CSS pseudo-class - CSS | MDN
The :user-valid CSS pseudo-class represents any validated form element whose value validates correctly based on its validation constraints. However, unlike...
valid cssuserpseudoclassmdn