Empty block regions are rendered

When a block region contains blocks that are empty for a user (e.g. Tools block and anonymous user), the region is rendered.

I placed the Tools block in Bottom First container, and the whole container is rendered (empty)

<div id="bottom-container" class="w3-col w3-clear w3-theme-l2 ">
        <div id="bottom-container-inner" class="w3-row-padding w3-padding-large bottom-container-inner ">
                          <!-- Start: Bottom First -->
              <div class="w3-col  first-bottom">
                <div class="d8-fade w3-card w3-round w3-mobile w3-theme-l4 " style="opacity: 1; transition: opacity 1s linear 0s;">
                  
                </div>
              </div>
              <!-- End: Bottom First -->
                                                        </div>
      </div>