[css-color-4] Be ass-clenchingly clear

Author: svgeesus

css-color-4/Overview.bs

@@ -5266,6 +5266,11 @@ Resolving sRGB values</h3>
 	or as a [=system color=],
 	the [=specified value=] is that named or system color, converted to 
 	<a href="https://infra.spec.whatwg.org/#ascii-lowercase">ASCII lowercase</a>.
+	The computed and used value
+	is the corresponding sRGB color,
+	paired with the specified alpha channel
+	(after clamping to [0.0, 1.0])
+	and defaulting to opaque if unspecified).
 
 	<div class="example" id="ex-named-case">
 			<p>The author-provided mixed-case form below has a specified value in all lowercase.</p>