_form.html.erb

<%= form_for([:management, @complaint_reason], html: {class: 'ls-form row'}) do |f| %>

    <% if @complaint_reason.errors.any? %>
        <div class="ls-alert-danger">
          <h2><%= pluralize(@complaint_reason.errors.count, "erro") %> <%= "happened".pluralize(@complaint_reason.errors.count) %>:</h2>
          <ul>
            <% @complaint_reason.errors.full_messages.each do |message| %>
                <li><%= message %></li>
            <% end %>
          </ul>
        </div>
    <% end %>

    <fieldset>
      <label class="ls-label col-md-3">
        <b class="ls-label-text">Razão</b>
        <p>Digite a razão</p>
        <%= f.text_field :reason, {required: true} %>
      </label>
    </fieldset>

    <div class="ls-actions-btn">
      <button class="ls-btn">Salvar</button>
      <%= link_to "Cancelar", management_complaint_reasons_path,class: "ls-btn-danger"%>
    </div>

<% end %>