anchor.diff:                td #{instance.students.length}
               tr
                 td Average level play time:
  -              td #{stats.averageLevelPlaytime} seconds
  +              td= moment.duration(stats.averageLevelPlaytime, "seconds").humanize()
               tr
                 td Total play time:
  -              td #{stats.totalPlayTime} seconds
  +              td= moment.duration(stats.totalPlayTime, "seconds").humanize()
               tr
                 td Average levels completed:
                 td #{stats.averageLevelsCompleted}
  
positive.code:                         div
                            - var playTime = Math.round(Math.random() * 600)
                            span Time to solve
                            span : #{playTime} seconds
                          div
                            - var completionDate = new Date()
                            - completionDate.setUTCDate(completionDate.getUTCDate() - Math.round(Math.random() * 60))
  
negative.code:           span &times;
          h3.modal-title Edit Class Settings
        .modal-body
          p
            strong Title
          p 
            input.edit-name-input(type='text', value="#{instance.name}")
          p
            strong Description
          p 
            textarea.edit-description-input(rows=2)= instance.description
          p Select programming languages available to the class:
  