anchor.diff: -<div class="card bg-mdb-color-lighten-4">
  +<div class="card bg-mdb-color-lighten-6">
     <div class="card-header">
       <h5>
         Vorlesungsinhalt
  
positive.code:               <li class="list-group-item bg-mdb-color-lighten-5">
                  <div class="row">
                    <div class="col-6">
                      <%= link_to s.to_label, section_path(s), class:'text-dark' %>
                    </div>
                    <div class="col-6">
                      <% s.lessons.each do |l| %>
  
negative.code:     <div class="card-columns">
        <% lecture.chapters.each do |c| %>
          <div class="card bg-mdb-color-lighten-5">
            <div class="card-header bg-mdb-color-lighten-2">
              <span class="text-light">
                <%= c.to_label %>
              </span>
            </div>
            <div class="card-body">
            <ul class="list-group list-group-flush">
  