CSS Style form elements ( :checked pseudo-class )

CSS Linear Gradient

CSS HSL and HSLA Colors

CSS RGB and RGBA Colors

CSS HEX Color

CSS Transparent & Currentcolor Keywords

CSS Named Colors

CSS selection Pseudo element

CSS marker Pseudo element

CSS first line Pseudo element

CSS placeholder Pseudo element

CSS first letter Pseudo element

CSS before and after Pseudo elements

CSS not() pseudo class

CSS is() and where() pseudo classes

has() CSS logical pseudo-class (how to style a parent element)

CSS Style form elements ( placeholder-shown pseudo-class )

CSS Style form elements ( valid and invalid pseudo classes )

CSS Style form elements ( :in-range and :out-of-range pseudo-classes )

CSS Style form elements ( :indeterminate pseudo-class )

CSS Style form elements ( :checked pseudo-class )

CSS Style form elements ( :Required and :optional pseudo classes )

CSS Style form elements ( :enabled and :disabled pseudo classes )

CSS typed child-indexed pseudo-classes

child indexed pseudo classes , CSS tutorial