Fix invalid input within docs

docs/css.html

@@ -1273,10 +1273,10 @@ For example, <code>&lt;section&gt;</code> should be wrapped as inline.
     </div>
 
     <form class="bs-example form-inline">
-      <input class="col col-lg-3" type="email" placeholder="test@example.com" required>
+      <input type="email" placeholder="test@example.com" required>
     </form>
 {% highlight html %}
-<input class="col col-lg-3" type="email" placeholder="test@example.com" required>
+<input type="email" placeholder="test@example.com" required>
 {% endhighlight %}
 
     <h3 id="forms-disabled-inputs">Disabled inputs</h3>