diff --git a/examples/jumbotron/index.html b/examples/jumbotron/index.html
index fcf7174c43..86255fca35 100644
--- a/examples/jumbotron/index.html
+++ b/examples/jumbotron/index.html
@@ -59,7 +59,7 @@
             <div class="form-group">
               <input type="password" placeholder="Password" class="form-control">
             </div>
-            <button type="submit" class="btn">Sign in</button>
+            <button type="submit" class="btn btn-success">Sign in</button>
           </form>
         </div><!--/.navbar-collapse -->
       </div>