[css-color-4] Modern hsl & hsla also allows mixed num-pct w3c#8231

Author: svgeesus

css-color-4/Overview.bs

@@ -1964,15 +1964,28 @@ HSL Colors: ''hsl()'' and ''hsla()'' functions</h2>
 
 	There are several other color schemes possible.
 	One such is the HSL [[!HSL]] color scheme,
-	which is much more intuitive to use,
+	which is more intuitive to use,
 	but still maps easily back to RGB colors.
 
 	<dfn value export for="hsl()">HSL</dfn> colors are specified
 	as a triplet of hue, saturation, and lightness.
-	The syntax of the ''hsl()'' function is:
+	The syntax of the ''hsl()'' and ''hsla()'' functions is:
 
 	<pre class='prod'>
-	<dfn>hsl()</dfn> = hsl( [<<hue>> | none] [<<percentage>> | none] [<<percentage>> | none] [ / [<<alpha-value>> | none] ]? )
+	<dfn>hsl()</dfn> = [ <<legacy-hsl-syntax>> | <<modern-hsl-syntax>> ]
+	<dfn>hsla()</dfn> = [ <<legacy-hsla-syntax>> | <<modern-hsla-syntax>> ]
+	<dfn><<modern-hsl-syntax>></dfn> = hsl( 
+			[<<hue>> | none] 
+			[<<percentage>> | <<number>> | none] 
+			[<<percentage>> | <<number>> | none] 
+			[ / [<<alpha-value>> | none] ]? )
+	<dfn><<modern-hsla-syntax>></dfn> = hsla( 
+			[<<hue>> | none] 
+			[<<percentage>> | <<number>> | none] 
+			[<<percentage>> | <<number>> | none] 
+			[ / [<<alpha-value>> | none] ]? )
+	<dfn><<legacy-hsl-syntax>></dfn> = hsl( <<hue>>, <<percentage>>, <<percentage>>, <<alpha-value>>? )
+	<dfn><<legacy-hsla-syntax>></dfn> = hsla( <<hue>>, <<percentage>>, <<percentage>>, <<alpha-value>>? )
 	</pre>
 
 	<wpt>
@@ -2117,17 +2130,8 @@ HSL Colors: ''hsl()'' and ''hsla()'' functions</h2>
 
 	</div>
 
-	For legacy reasons,
-	''hsl()'' also supports a <a>legacy color syntax</a>
-	that separates all of its arguments with commas:
-
-	<pre class='prod'>
-	hsl() = hsl( <<hue>>, <<percentage>>, <<percentage>>, <<alpha-value>>? )
-	</pre>
-
-	Also,
-	an <dfn>hsla()</dfn> <a>legacy color syntax</a> also exists,
-	with an identical grammar and behavior to ''hsl()''.
+	For historical reasons,
+	''hsl()'' and ''hsla()'' also support a <a>legacy color syntax</a>.
 
 	<wpt>
 		hsla-001.html