[Theme Horse Support Team]

Hi Elodie,

You have to add below html code manually to have the promobox inside the pages.

<section class="widget widget_promotional_bar clearfix">
  <div class="promotional-text">“Free Responsive Retina Ready WordPress Theme”
    <span>Free WordPress Theme has never been so easy & beautiful.</span>
  </div>
  <a title="View Work" href="#" class="call-to-action">View Work</a>
 </section>

And to manage it on center Go to Appearance -> Theme Options -> Design Options Tab -> Custom CSS paste the following CSS code and Click on save all changes button:

.widget_promotional_bar {
    text-align: center;
}
.widget_promotional_bar .promotional-text {
    float: none;
    text-align: center;
    width: 100%;
}
.widget_promotional_bar .call-to-action {
    float: none;
    margin-top: 16px;
}

Thank you!