Add pure css grids

app/views/layouts/application.html.haml

@@ -7,6 +7,8 @@
     = javascript_include_tag 'application', 'data-turbolinks-track' => true
     = csrf_meta_tags
   %body
+    .pure-g
+      .pure-u-1
         .pure-menu.pure-menu-horizontal
           %ul.pure-menu-list
             - if current_user
@@ -16,5 +18,6 @@
                 = link_to "New Transaction", new_transaction_path, class: "pure-menu-link"
             - else
               = link_to "Sign in", user_omniauth_authorize_path(:zeuswpi), class: "pure-menu-link" unless current_user
+      .pure-u-1
         = render 'partials/flash'
         = yield