ruby on rails - @Simple_form rendering but not showing *SOLVED* -

i switched rails , started on first application. im struggling bit forms , bootstrap however! says form rendering , im not receiving errors, none of form code showing. im running rails 4.2.5 latest bootstrap-sass , simple_form versions. im not sure whether bootstrap css working @ either, doesnt appear be. been trying different versions, installing , uninstalling , changing code hours canẗ seem working. immensely grateful help!

kind regards, jens

form (_form.html.erb) code;

<%= simple_form_for @book, html: ({ cĺass:'form-horizontal'}) |f| %> <div class = "field"> <%= f.input :title, label: "book title" %> <%= f.input :description %> <%= f.input :author %> <%= f.button :submit %>  <% end %> 

i renamed application.css .scss, contains only; @import "bootstrap-sprockets"; @import "bootstrap"; application.js contains:

//= require jquery //= require jquery_ujs //= require bootstrap-sprockets //= require turbolinks //= require_tree . 

your code partial calling from? needs rendered inside of file index.html.erb.

whenever name starts _ means partial not full page, rendered inside page.

also there's div doesn't end in code why use div class when can pass in through rails ? class: "field" or along lines.