m: style example table to accomodate sample rendering PNGs

Author: Tantek Çelik

css3-ui/Overview.html

@@ -2979,7 +2979,7 @@ <h5 class="no-num no-toc" id=sample-css-for-a-div>sample CSS for a div:</h5>
     id=sample-html-fragments-renderings-and-you>sample HTML fragments,
     renderings, and your browser:</h5>
 
-   <table border=1 cellpadding=5>
+   <table border=1 cellpadding=5 style="color:#000;background:#fff;">
     <tbody>
      <tr>
       <th>HTML

css3-ui/Overview.src.html

@@ -1596,7 +1596,7 @@ <h5 class="no-num no-toc">sample CSS for a div:</h5>
   width:3.2em; padding:.2em; border:solid .1em black; margin:1em 0;
 }</code></pre>
 <h5 class="no-num no-toc">sample HTML fragments, renderings, and your browser:</h5>
-<table border="1" cellpadding="5"><tbody>
+<table border="1" cellpadding="5" style="color:#000;background:#fff;"><tbody>
 <tr><th>HTML</th><th>sample rendering</th><th>your browser</th></tr>
 <tr>
 <td><pre><code>&lt;div&gt;