Better login screen labels

app/views/devise/sessions/new.html.haml

-%h2 Log in
-= form_for(resource, as: resource_name, url: session_path(resource_name)) do |f|
-  .field
-    = f.label :email
-    %br/
-    = f.text_field :login, autofocus: true, autocomplete: 'login'
-  .field
-    = f.label :password
-    %br/
-    = f.password_field :password, autocomplete: 'current-password'
-  - if devise_mapping.rememberable?
-    .field
-      = f.check_box :remember_me
-      = f.label :remember_me
-  .actions
-    = f.submit 'Log in'
+%h2= t '.title'
+%fieldset
+  = form_for(resource, as: resource_name, url: session_path(resource_name)) do |f|
+    .field.login
+      = f.label :login
+      %br/
+      = f.text_field :login, autofocus: true, autocomplete: 'login'
+    .field.password
+      = f.label :password
+      %br/
+      = f.password_field :password, autocomplete: 'current-password'
+    - if devise_mapping.rememberable?
+      .field
+        = f.check_box :remember_me
+        = f.label :remember_me
+    .actions
+      = f.submit t('.sign_in')
+
 = render 'devise/shared/links'