我的HTML：

<ul class="navbar-nav ms-auto mb-2 mb-lg-0">
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" style="color: #fff;" href="#" id="navbarDropdownMenuLink" role="button" data-bs-toggle="dropdown" aria-expanded="false">CURTAINS </a>
          <ul class="dropdown-menu columns" aria-labelledby="navbarDropdownMenuLink">
               <p class="sub dropdown-item">Curtains</p>
            <li><a class="dropdown-item" href="#">Ready-Made Curtains</a></li>
            <li><a class="dropdown-item" href="#">Custom-Made Curtains</a></li>
            <li><a class="dropdown-item" href="#">Made To Measure Curtains</a></li>
            <li><a class="dropdown-item" href="#">Blockout curtains</a></li>
            <li><a class="dropdown-item" href="#">Thernal Curtains</a></li>
            <li><a class="dropdown-item" href="#">Wave Fold Curtains</a></li>
            <li><a class="dropdown-item" href="#">Sheer Curtains</a></li>
            <li><a class="dropdown-item" href="#">Eyelet Curtains</a></li>
            <li><a class="dropdown-item" href="#">Pinch Pleat Curtains</a></li>
            <li><a class="dropdown-item" href="#">Blockout Eyelet Curtains</a></li>
            <li><a class="dropdown-item" href="#">Pinch Pleat Blockout Curtains</a></li>
            <li><a class="dropdown-item" href="#">Pencil Pleat Curtains</a></li>
            <li><a class="dropdown-item" href="#">Home Theatre Curtains</a></li>
            <li><a class="dropdown-item" href="#">Decorator Curtains</a></li>
            <li><a class="dropdown-item" href="#">Kids Curtains</a></li>
            <li><a class="dropdown-item" href="#">Extra Long Curtains</a></li>
            <li><a class="dropdown-item" href="#">Bulk Buy Curtains</a></li>
            <li><a class="dropdown-item" href="#">Design Your Own Curtains</a></li>
            <li><a class="dropdown-item" href="#">Curtain Sale Curtains</a></li>
            <li><a class="dropdown-item" href="#">Velvet Curtains</a></li>
            <li><a href="#"><img class="dropdown-img" src="https://images.pexels.com/photos/969593/pexels-photo-969593.jpeg?auto=compress&cs=tinysrgb&dpr=1&w=500" alt=""></a></li>
            <li><a href="#"><img class="dropdown-img" src="https://images.pexels.com/photos/969593/pexels-photo-969593.jpeg?auto=compress&cs=tinysrgb&dpr=1&w=500" alt=""></a></li>
          </ul>