[css-color]define handling on mismatched numerical parameters

Author: svgeesus

css-color/Overview.bs

@@ -1663,7 +1663,7 @@ gamut space capable of representing almost all visible real-world colors. Both a
 <div class='example'>
 	This example specifies four profiled colors: for a standard CMYK press, for a wide-gamut 
 	seven-ink printer, for ProPhoto RGB, and for the P3 standard RGB space. 
-	
+	<!-- add examples with alpha, and with fallback -->
 	<pre>
 		color(swopc, 0, 206 190 77);
 		color(indigo, 24 160 86 42 0 18 31);
@@ -1686,9 +1686,10 @@ gamut space capable of representing almost all visible real-world colors. Both a
 
 <h3 id="color-function">Specifying profiled colors: the ''color()'' function</h3>
 
-The color function takes an indentifier as the first parameter, followed by as many 
+The color function takes an indentifier as the first parameter, followed by either as many 
 numerical parameters as are needed (three for an RGB colorspace, four for CMYK, 
-one for greyscale, and so on). An optional, comma-separated alpha value is also supported.
+one for greyscale, and so on) or a quoted string (for named color profiles). 
+An optional, comma-separated alpha value is also supported.
 The identifier is either one of the predefined spaces 
 (<i>p3</i> or <i>rec2020</i>) or the name of a profile. An optional fallback may be specified
 (an sRGB color, or indeed another color() function).
@@ -1697,14 +1698,15 @@ The identifier is either one of the predefined spaces
 	like AdobeRGB, ProPhoto RGB, and so on. Also coated and uncoated swop, etc, etc. </pre>
 
 	<pre class='prod'>
-		<dfn>color()</dfn> = color( <<ident>> , <<number>>+ [, <<alpha-value>>]? [, <<fallback>>]?)
+		<dfn>color()</dfn> = color( <<ident>> , [<<number>>+ | <<string>>] [, <<alpha-value>>]? [, <<fallback>>]?)
 	</pre>
 
-	<p class="issue">How to handle cases where there are too many, or too few, numbers supplied?
-		Seems like ignoring extra numbers, and treating unspecified numbers ar zero, would be 
-		the most robust?</p>
+	<p>If too many numbers are supplied, the first ones are used and the rest are silently ignored.
+		If too few numbers are supplied, unspecified numbers are considered to be zero.
+		This is convenient particularly for multichannel printers where the additional inks 
+		are spot colors or varnishes and not used for most colors.</p>
 
-	<p class="issue">Need a fallback color, as decided at San Francisco. Add after the alpha value.
+	<p class="issue">Further define a fallback color, as decided at San Francisco. 
 		Can be an sRGB fallback or indeed another color() function.</p>
 
 	<p class="issue">Need to add choice of quoted string or number+, to allow f