Use class=panel for message_area on /login.

frontends/etiquette_flask/templates/login.html

@@ -86,7 +86,7 @@ form h2
             <input type="password" id="register_input_password_2" name="password_2" placeholder="password again">
             <button type="submit" id="register_input_button" class="green_button" onclick="return register_form(event);">Register</button>
         </form>
-        <div id="message_area">
+        <div id="message_area" class="panel">
         </div>
     </div>
 </body>