* ability to select specific "pieces" of any compound/composite form control for styling
** feeds into requirements for CSS pseudo-elements
** consider existing UI pseudo-elements*** [http://www.w3.org/TR/css3-ui/#pseudo-elements ::value ::choices ::repeatCSS3-item ::repeatUI pseudo-indexelements]**** ::value in particular can be used for selecting/styling placeholder text (see [https://bugzilla.mozilla.org/show_bug.cgi?id=457801#c25 bug 457801 comment 25]).*** ::choices *** ::repeat-item *** ::repeat-index
* ability to select specific "states" of any form control (may require ability to select states of specific pieces as well - that will be a challenge though as pseudo-elements themselves cannot have pseudo-classes in CSS)
** existing [http://www.w3.org/TR/css3-selectors/#UIstates Selectors UI pseudo-classes], and some notes on [http://www.w3.org/TR/html5/interactive-elements.html#pseudo-classes how HTML5 DOM property states trigger these pseudo-classes]