add second example

Author: svgeesus

css-color-5/Overview.bs

@@ -47,9 +47,15 @@ Mixing colors: the ''color-mix'' function {#colormix}
 	in a given colorspace,
 	by a specified amount.
 
+	Unless otherwise specified,
+	the mixing is done in the ''lch()'' colorspace.
+
+	Multiple color functions can be specified.
+
 
 <pre class='prod'>
-	<dfn>color-mix()</dfn> = color-mix( <<color>>  <<color>> [ <<color-function>> <<colorspace>>? ]? )
+	<dfn>color-mix()</dfn> = color-mix( <<color>>  <<color>>
+		[ <<number-percent>> | <<color-function>> <<colorspace>>? ]? )
 </pre>
 
 <div class="example">
@@ -62,10 +68,36 @@ Mixing colors: the ''color-mix'' function {#colormix}
 	<pre class="lang-css">mix-color(red, yellow, lightness(30%));</pre>
 
 	The calculation is as follows:
-	  * sRGB red (#F00) is lch(54.2917, 106.8390, 40.8526)
-	  * sRGB yellow (#FF0) is lch(97.6071, 94.7077, 99.5746)
-	  * mix lightness is 54.2917*.3 + 97.6071*.7 = 84.6125
-	  * mixed result is lch(84.6125, 106.8390, 40.8526)
-	  * which is a very light red (and outside the gamut of sRGB: rgb(218.081%, 22.5941%, 8.72667%))
+	  * sRGB red (#F00) is lch(54.2917 106.8390 40.8526)
+	  * sRGB yellow (#FF0) is lch(97.6071 94.7077 99.5746)
+	  * mix lightness is 54.2917 * 0.3 + 97.6071 * 0.7 = 84.6125
+	  * mixed result is lch(84.6125 106.8390 40.8526)
+	  * which is a very light red (and outside the gamut of sRGB: rgb(140.4967% 51.2654% 32.6891%))
 </div>
 
+Instead of a list of color functions,
+a plain number or percentage can be specified,
+which applies to all color channels.
+
+<div class="example">
+		This example produces the mixture of red and yellow,
+		in ''lch'' colorspace (the default),
+		with each lch channel being 65% of the value for red
+		and 35% of the value for yellow.
+
+		Note: interpolating on hue and chroma
+		keeps the intermediate colors
+		as saturated as the endpoint colors.
+
+		<pre class="lang-css">mix-color(red, yellow, 65%);</pre>
+
+		The calculation is as follows:
+		  * sRGB red (#F00) is lch(54.2917 106.8390 40.8526)
+		  * sRGB yellow (#FF0) is lch(97.6071 94.7077 99.5746)
+		  * mix lightness is 54.2917 * 0.65 + 97.6071 * 0.35 = 69.4521
+		  * mix chroma is 106.83 * 0.65 + 94.7077 * 0.35 = 102.5872
+		  * mix hue is 40.8526 * 0.65 + 99.5746 * 0.35 = 61.4053
+		  * mixed result is lch(69.4521 102.5872 61.4053)
+		  * which is a red-orange: rgb(75.3600% 65.6304% 16.9796%)
+	</div>
+