body{background:#f1f1f1;font-family:Arial}.banner-topo{display:flex;gap:10px;justify-content:center;margin:10px 0;flex-wrap:wrap}.banner728{width:728px;height:90px;background:#ddd;display:flex;align-items:center;justify-content:center}.container{display:grid;grid-template-columns:3fr 1fr;gap:20px}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:15px}.ad{width:300px;height:250px;background:#ccc;margin-bottom:15px;display:flex;align-items:center;justify-content:center}