<div class='row'>
  <div class='col-lg-6 col-lg-offset-3'>
    <div class='panel panel-default'>
      <div class='panel-heading'>
        <h3 class='panel-title'>Search</h3>
      </div>
      <div class='panel-body'>
        <%= form_tag(works_path, method: :get, id: "search-form") do %>
          <div class='input-group'>
            <%= text_field_tag :search, '', class: 'form-control' %>
            <span class="input-group-btn">
              <%= submit_tag "Go!", class: 'btn btn-secondary' %>
            </span>
          </div>
        <% end %>
      </div>
    </div>
  </div>
</div>
<div class='row'>
  <div class='col-lg-6 col-lg-offset-3'>
    <div class='panel panel-default'>
      <div class='panel-heading'>
        <h3 class='panel-title'>Search</h3>
      </div>
      <div class='panel-body'>
        <%= form_tag(works_path, method: :get, id: "search-form") do %>
          <div class='input-group'>
            <%= text_field_tag :search, params[:search], class: 'form-control' %>
            <span class="input-group-btn">
              <%= submit_tag "Go!", class: 'btn btn-secondary' %>
            </span>
          </div>
        <% end %>
      </div>
    </div>
  </div>
</div>
Use last search term in placeholder
Use last search term in placeholder

This will make it easier for users to keep track of what they searched
for, or modify their previous search, etc.
