如何将垂直子菜单项与父菜单对齐

我有一个垂直菜单，显示悬浮在子菜单项。我想根据父菜单项对齐子菜单。我带来的菜单和子菜单项通过中继器。我希望子菜单是响应的，如所示的图像。使用此链接，例如:http://www.industrybuying.com/

    <div class="vertical-menu-content">
                                <ul class="vertical-menu-list">
                                    <asp:Repeater ID="rptVerticalMenu" runat="server" OnItemDataBound="rptVerticalMenu_ItemDataBound">
                                        <ItemTemplate>
                                            <li class="vertical-menu4">
                                                <a href="Product_List.aspx?cat=<%#Eval("BasicCategoryName")%>" class="parent linkSize">
                                                    <asp:Label ID="lblCatList" runat="server" Text='<%#Eval("BasicCategoryName")%>'></asp:Label>
                                                </a>
                                                <div class="vertical-dropdown-menu">
                                                    <div class="vertical-groups">
                                                        <div class="row">
                                                            <div class="col-sm-4">
                                                                <div class="block-content-vertical-menu border-left">
                                                                    <h3 class="head">CATEGORIES</h3>
                                                                    <div class="inner">
                                                                        <ul class="vertical-menu-link">
                                                                            <asp:Repeater ID="rptVerticalSubMenu" runat="server">
                                                                                <ItemTemplate>
                                                                                    <li>
                                                                                        <a href="Product_List.aspx?cat=<%#Eval("CategoryName")%>">
                                                                                            <asp:Label ID="lblCatName" runat="server" CssClass="text" Text='<%#Eval("CategoryName")%>'></asp:Label>
                                                                                        </a>
                                                                                    </li>
                                                                                </ItemTemplate>
                                                                            </asp:Repeater>
                                                                        </ul>
                                                                    </div>
                                                                </div>
                                                            </div>
                                                           <%-- <div class="col-sm-4">
                                                                <div class="block-content-vertical-menu border banner-hover">
                                                                    <a href="#">
                                                                        <img src="WebTheme/TransMax/data/banner/b42.png" alt="Banner"></a>
                                                                </div>
                                                            </div>--%>
                                                        </div>
                                                    </div>
                                                </div>
                                            </li>
                                        </ItemTemplate>
                                    </asp:Repeater>

                                </ul>
                            </div>

.vertical-menu-list, .vertical-menu-link, h3{
    margin: 5px;
    padding:5px;
}

ul, h3{
    margin: 5px;
    padding:5px;
}