anchor.diff:  
         <div class="form-group">
           <%= f.label :c_6, "С-6", class: "col-sm-2 control-label"  %>
  -        <div class="col-sm-1">
  +        <div class="col-sm-2 col-lg-1">
             <%= f.select :c_6, %w[0 1 2 3], {}, {class: "form-control"} %>
           </div>
         </div>
  
positive.code: 
        <div class="form-group">
          <%= f.label :dop_3, "DOP-3", class: "col-sm-2 control-label"  %>
          <div class="col-sm-1">
            <%= f.select :dop_3, %w[1 2 3], {}, {class: "form-control"} %>
          </div>
        </div>
        <div class="form-group">
          <%= f.label :dop_4, "DOP-4", class: "col-sm-2 control-label"  %>
          <div class="col-sm-1">
            <%= f.select :dop_4, %w[1 2 3], {}, {class: "form-control"} %>
          </div>
        </div>
        <div class="form-group">
          <%= f.label :dop_5, "DOP-5", class: "col-sm-2 control-label"  %>
          <div class="col-sm-1">
            <%= f.select :dop_5, %w[1 2 3], {}, {class: "form-control"} %>
          </div>
        </div>
  
negative.code: 
        <div class="form-group">
          <%= f.label :c_4, "С-4", class: "col-sm-2 control-label"  %>
          <div class="col-sm-2 col-lg-1">
            <%= f.select :c_4, %w[0 1 2 3], {}, {class: "form-control"} %>
          </div>
        </div>
  