anole docs - anchorpoints
Use an-anchorpoints as internal bookmarks for your webpage. They area not meant to have any visible content by default. All anchorpoints must contain a div, which does the actual work of "anchoring." This is due to limitations in CSS and HTML. The outer div is positioned relatively, and the inner div is positioned absolutely.
<div class="an-anchorpoint">     <div id="anchorpoint"></div> </div>