Question

Yo everyone

My question is quite simple: I need to style the red border (or shadow?) of the inputs that couldn’t be validated (like email). Is there any new CSS trick to do that?

If you still don’t understand what I am telling you, then this is the color that needs changing:

Answer 1

See https://developer.mozilla.org/en/CSS/%3Ainvalid for Firefox details, although presumably the parts without “-moz” apply to other browsers too:

The :invalid CSS pseudo-class is applied automatically to <input>
elements whose contents fail to validate according to the input’s type
setting. This allows you to easily have invalid fields adopt an
appearance that helps the user identify and correct errors.

By default, Gecko does not apply a style to the :invalid pseudo-class.
However it does apply a style (a red “glow” using the box-shadow
property) to the :-moz-ui-invalid pseudo-class, which applies in a
subset of cases for :invalid.