[css-color-4] Modern rgb & rgba also allows mixed num-pct #8231

Author: svgeesus

css-color-4/Overview.bs

@@ -1134,12 +1134,22 @@ sRGB Colors</h2>
 <h3 id='rgb-functions'>
 The RGB functions: ''rgb()'' and ''rgba()''</h3>
 
-	The ''rgb()'' function defines an sRGB color by specifying the red, green, and blue channels directly.
-	Its syntax is:
+	The ''rgb()'' and ''rgba()'' functions define an sRGB color by specifying the red, green, and blue channels directly.
+	Their syntax is:
 
 	<pre class='prod'>
-	<dfn>rgb()</dfn> = rgb( [<<percentage>> | none]{3} [ / [<<alpha-value>> | none] ]? ) |
-	  rgb( [<<number>> | none]{3} [ / [<<alpha-value>> | none] ]? )
+	<dfn>rgb()</dfn> = [ <<legacy-rgb-syntax>> | <<modern-rgb-syntax>> ] 
+	<dfn>rgba()</dfn> = [ <<legacy-rgba-syntax>> | <<modern-rgba-syntax>> ] 
+	<dfn><<legacy-rgb-syntax>></dfn> = 	rgb( <<percentage>>#{3} , <<alpha-value>>? ) |
+										rgb( <<number>>#{3} , <<alpha-value>>? )
+	<dfn><<legacy-rgba-syntax>></dfn> = rgba( <<percentage>>#{3} , <<alpha-value>>? ) |
+										rgba( <<number>>#{3} , <<alpha-value>>? )
+	<dfn><<modern-rgb-syntax>></dfn> = rgb( 
+		[ <<number>> | <<percentage>> | none]{3} 
+		[ / [<<alpha-value>> | none] ]?  )
+	<dfn><<modern-rgba-syntax>></dfn> = rgba( 
+		[ <<number>> | <<percentage>> | none]{3} 
+		[ / [<<alpha-value>> | none] ]?  )
 	</pre>
 
 	<wpt>
@@ -1182,18 +1192,8 @@ The RGB functions: ''rgb()'' and ''rgba()''</h3>
 	Values outside these ranges are not invalid,
 	but are clamped to the ranges defined here at parsed-value time.
 
-	For legacy reasons,
-	''rgb()'' also supports a <a>legacy color syntax</a>
-	that separates all of its arguments with commas:
-
-	<pre class='prod'>
-	rgb() = rgb( <<percentage>>#{3} , <<alpha-value>>? ) |
-	  rgb( <<number>>#{3} , <<alpha-value>>? )
-	</pre>
-
-	Also,
-	an <dfn>rgba()</dfn> <a>legacy color syntax</a> also exists,
-	with an identical grammar and behavior to ''rgb()''.
+	For historical reasons,
+	''rgb()'' and ''rgba()'' also support a <a>legacy color syntax</a>.
 
 	<wpt>
 		rgba-001.html