#sidebar {
  width: 250px;
  background: #fff;
}
  .sidebar_banner {
    width: 100%;
  }
  .sidebar_head {
    width: 100%;
    margin-top: 8px;
    padding: 5px 0 5px 10px;
    background: #19a78e;
    color: #fff;
    font-weight: bold;
  }
  .sidebar_list {
    width: 100%;
    margin-bottom: 8px;
    padding: 5px;
    border: solid 1px #19a78e;
  }
    .sidebar_list img  {
      max-width: 100%;
    }
    .sidebar_list_item {
      display: block;
      margin-top: 10px;
    }
      .sidebar_list_item img {
        width: 100%;
        max-height: 80px;
        object-fit: cover;
      }
      /* polyfill */
      _:lang(x)::-ms-backdrop,.sidebar_list_item img {
        font-family: 'object-fit: cover;'; 
      }
  
  #sidebar .article-list_list_item {
    width: 100%;
  }

@media screen and (max-width: 768px) {
  #sidebar {
    display: none;
  }
}