anchor.diff:          <li>
             <%= icon('check-square', '', class: 'fa-li') %>
             Compatibility with
  -          <strong><%= link_to 'Bootstrap v3', 'http://getbootstrap.com' %></strong> and
  +          <strong><%= link_to 'Bootstrap v4', 'http://getbootstrap.com' %></strong> and
             <strong><%= link_to 'Font Awesome v4', 'http://fortawesome.github.io/Font-Awesome/' %></strong>
           </li>
           <li>
  
positive.code:       <%= image_tag('700x300.gif', class: 'img-responsive img-thumbnail') %>
      </div>
    </div>
  
    <div class='row'%>
      <div class='col-lg-12'>
  
negative.code:     %>
    </div>
  
    <hr>
  
    <div class='row'>
      <div class='col-lg-12'>
        <h2 class='pt-4'>Main features</h2>
  