fix broken markup

Author: Florian Rivoal

css3-mediaqueries/Overview.html

@@ -1097,9 +1097,8 @@ <h3 id=grid><span class=secno>4.13. </span>grid</h3>
   <div class=example>
    <p>Here are two examples:</p>
 
-   <pre><code>@media handheld and (grid) and (max-width: 15em) { &hellip; }
-<span
-    class=css-example>@media handheld and (grid) and (device-max-height: 7em) { &hellip; }</span></code></pre>
+   <pre><code>@media handheld and (grid) and (max-width: 15em) { &hellip; }</code>
+<code>@media handheld and (grid) and (device-max-height: 7em) { &hellip; }</code></pre>
   </div>
 
   <h2 id=values><span class=secno>5. </span>Values</h2>

css3-mediaqueries/Overview.src.html

@@ -957,8 +957,8 @@ <h3 id="grid">grid</h3>
 
 <p>Here are two examples:</p>
 
-<pre><code>@media handheld and (grid) and (max-width: 15em) { &hellip; }</span>
-<span class="css-example">@media handheld and (grid) and (device-max-height: 7em) { &hellip; }</code></pre>
+<pre><code>@media handheld and (grid) and (max-width: 15em) { &hellip; }</code>
+<code>@media handheld and (grid) and (device-max-height: 7em) { &hellip; }</code></pre>
 
 </div>