Here\'s what I\'ve tried, and the simple_form_for call ignored my class setting.
simple_form_for
# Rails code in view: <%= simple_form_for @admin_artist, :cl
this would work
<%= simple_form_for @admin_artist, :html=> { class: 'foobarbaz' } do |f| %>
You should use :html like this:
:html
<%= simple_form_for @admin_artist, :html => { role: 'form', class: 'foobarbaz' } do |f| %>