The module preprocessor doesn't like the example

  content: 'this is a \'string\'';

so I added a period between the two quotes...

Author: bert-github

css3-values/Overview.src.html

@@ -187,10 +187,10 @@ <h3>Strings</h3>
 
 <div class=example>
 <pre>
-content: "this is a 'string'";
-content: "this is a \"string\"";
-content: 'this is a "string"';
-content: 'this is a \'string\'';
+content: "this is a 'string'.";
+content: "this is a \"string\".";
+content: 'this is a "string".';
+content: 'this is a \'string\'.';
 </pre>
 </div>