title: Styling file upload button for simple_form_for with Bootstrap in Rails 3
body: <p>Using simple_form_for, Bootstrap and Rails 3. In a form: </p>
  
  <p><code>&lt;%= f.input :upload, label: 'PDF file:' , input_html: {accept: ('application/pdf') } %&gt;</code></p>
  
  <p>I don't know how I'd style this so that the "choose file" button can have a different class ('btn btn-primary').</p>
  
  <p>Additionally, when using with Bootstrap at least, its severely misaligned by default. See attached image.</p>
  
  <p>Finally, how do I redefine the text from "No file chosen" to "Chose file" when there isn't one added yet, and show the file name when there is one. </p>
  
  <p><img src="https://i.stack.imgur.com/fNhf4.png" alt="enter image description here"></p>