Resolve issue 21 by linking to appearance property.

Author: dbaron

css3-color/Overview.html

@@ -4661,8 +4661,10 @@ <h4 id=css2-system><span class=secno>4.5.1. </span>CSS2 System Colors</h4>
    keyword value is the keyword itself.
 
   <p>The CSS2 System Color values have been deprecated in favor of the CSS3
-   UI &lsquo;<code class=property>appearance</code>&rsquo; property for
-   specifying the complete look of user interface related elements.
+   UI &lsquo;<code class=css><a class=index-inst
+   href="http://www.w3.org/TR/css3-ui/#appearance"
+   id=appearance>appearance</a></code>&rsquo; property for specifying the
+   complete look of user interface related elements.
 
   <h3 id=notes><span class=secno>4.6. </span>Notes on using colors</h3>
 
@@ -5112,6 +5114,8 @@ <h2 class=no-num id=index>Index</h2>
     href="#ltalphavaluegt" title="&lt;alphavalue&gt;">4.2.2.</a>, <a
     href="#ltalphavaluegt0" title="&lt;alphavalue&gt;">4.2.5.</a>
 
+   <li>appearance, <a href="#appearance" title=appearance>4.5.1.</a>
+
    <li>color, <a href="#color0" title=color><strong>3.1.</strong></a>, <a
     href="#ltcolorgt" title="&lt;color&gt;">3.1.</a>, <a
     href="#valuea-def-color" title="&lt;color&gt;"><strong>4.</strong></a>

css3-color/Overview.src.html

@@ -1694,7 +1694,7 @@ <h4 id="css2-system">CSS2 System Colors</h4>
 <p class="note"><strong>Note.</strong> The computed value of a System Color 
 keyword value is the keyword itself.</p>
 
-<p>The CSS2 System Color values have been deprecated in favor of the CSS3 UI 'appearance' property for specifying the complete look of user interface related elements.</p>
+<p>The CSS2 System Color values have been deprecated in favor of the CSS3 UI '<a href="http://www.w3.org/TR/css3-ui/#appearance" class="index-inst">appearance</a>' property for specifying the complete look of user interface related elements.</p>
 
 
 <h3 id="notes">Notes on using colors</h3>