$forall (Entity challengeId challenge) <- challenges
  <div class="panel panel-success">
     <div class="panel-heading"><a .challenge-link  href="@{ShowChallengeR (challengeName challenge)}">#{challengeTitle challenge}</a>
        $if challengeStarred challenge
           \ <span class="glyphicon glyphicon-star-empty"></span>
     $if isJust (challengeImage challenge)
        <div class="panel-body" style="background-image:url(@{ChallengeImageR challengeId}); background-color:lightgrey; background-blend-mode:screen;background-size: 100%;">#{challengeDescription challenge}
     $else
        <div class="panel-body">#{challengeDescription challenge}