@page {
    size: a4 portrait;
    @frame content_frame {
        left: 25pt; width: 550pt; top: 10pt; height: 850pt;
    }
    @frame footer_frame {
        -pdf-frame-content: footer_content;
        left: 50pt; width: 512pt; top: 750pt; height: 200pt;
    }
}

<div id="footer_content">
<hr>
<p align="center">
    www.site.com.br <br/>

</p>