title: Access 'data-' attribute without jQuery
body: <p>Can I access a data- attribute without jQuery?</p>
  
  <p>It's easy with jQuery, but I can't see anywhere how to do it without jQuery.</p>
  
  <p>If I search on Google 'without jQuery' all I get is jQuery examples.</p>
  
  <p>Is it even possible?</p>