Fix minor mistake on the HTML

Author: mrego

index.html

@@ -80,7 +80,7 @@ <h4 class="list-group-item-heading">Simple grid example</h4>
                                     <a href="simple.html" class="label label-primary">example</a>
                                     <a href="https://github.com/Igalia/css-grid-layout/blob/gh-pages/simple.html" class="label label-success">html</a>
                                     <a href="https://github.com/Igalia/css-grid-layout/blob/gh-pages/simple.png" class="label label-info">screenshot</a>
-<                                    <a href="http://www.w3.org/TR/css-grid/#track-sizing" class="label label-warning">spec</a>
+                                    <a href="http://www.w3.org/TR/css-grid/#track-sizing" class="label label-warning">spec</a>
                                 </p>
                                 <p>Very simple 2x2 grid with fixed breadths.</p>
                             </li>