       }

        .item {
          list-style: none;
          background-color: green;
        }

        .item:nth-child(2),
        .item:nth-child(3),
        .item:nth-child(6),
        .item:nth-child(7),
        .item:nth-child(10) {
            @apply(--app-grid-expandible-item);
        }

      </style>

      <ul class="app-grid">
        <template items="[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]" is="dom-repeat">
          <li class="item">[[item]]</li>
        </template>
      </ul>

  