nel-heading">{{ book.title }}</h4>
            <div class="panel-body">
              <div class="row">
                <div class="col-md-4 col-xs-12 center">
                  <img src="{{ book.cover }}" alt="cover" class="img-thumbnail">
                </div>
                <div class="col-md-8 col-xs-12">
                  <table class="table table-bordered">
                    <tbody>
                      <tr><td style="width:80px;">作者</td><td>{{ book.author }}</td></tr>
                      <