:nail_care:, yes, but makes the code more readable and doesn't change the `html_classes` object.

```ruby
def html_classes_for_msg(name, is_persistent)
  html_classes = "#{name} alert-box animated"
  html_classes + if is_persistent
    ' persistent large-10 columns large-centered'
  else
    ' dismissible alert-box animated fadeIn text-center'
  end
end
```