.nn-sidebar-banner{margin:20px 0;min-height:250px;border:1px dashed #bbb;background:#fafafa;display:flex;align-items:center;justify-content:center}.banner-1{position:relative}
.banner-2{margin-top:20px;min-height:250px;border:1px dashed #999;background:#f8f8f8}
.banner-3{margin-top:20px;min-height:250px;border:1px dashed #888;background:#f6f6f6}