[css-ui-4] Generalize wording around application of accent-color. w3c#5187

Author: fantasai

css-ui-4/Overview.bs

@@ -1804,7 +1804,7 @@ Not every control uses the [=accent color=] in every state,
 but it is nonetheless a core part of the controls’ color scheme.
 
 The 'accent-color' CSS property allows the author to specify the [=accent color=]
-for user-interface controls represented by the element.
+for user-interface controls generated by the element.
 Values have the following meanings:
 
 <dl dfn-for=accent-color dfn-type=value>
@@ -1819,7 +1819,7 @@ Values have the following meanings:
 </dl>
 
 The UA should use the specified 'accent-color'
-to draw whichever parts of the form control
+to draw whichever parts of the element’s control(s)
 would have otherwise been styled with an [=accent color=].
 The UA must maintain contrast for legibility of the control,
 and in order to do so