Server control lost its CSS style when update panel is used
<p>I am using <a href="http://themeforest.net/item/mango-slick-responsive-admin-template/2728748?sso?WT.ac=category_item&amp;WT.seg_1=category_item&amp;WT.z_author=Stammi" rel="nofollow">this</a> template for my project. I have used updatepanel in the form and inside the update panel I have taken different dropdownlist control of asp.net. Now the issue is when the page get post back the css style apply to the dropdown gets lost...
As I have no detail idea about the CSS.. So please help</p>

<p>Now there are 2 possibility</p>

<ul>
<li>Not to apply css to the dropdown at all</li>
<li>apply CSS to the dropdown after postback</li>
</ul>

<p>If i simply drag and drop the dropdown control to the form the dropdown appears with the css.</p>

<p>I also used masterpage of this...I don't want to apply css to the dropdown... what to do then..
Please suggest me...</p>

<p><strong>Image when page loads</strong></p>

<p><img src="http://i.stack.imgur.com/cLo3t.png" alt="enter image description here"></p>

<p><strong>Image after postback( if updatepanel is used)</strong>
<img src="http://i.stack.imgur.com/6jE22.png" alt="enter image description here"></p>

<p><strong>.aspx code</strong></p>

<pre><code>&lt;asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server"&gt;
  &lt;div class="s" runat="server" id="divError"&gt;
        &lt;div class="round"&gt;
            &lt;span&gt;
                &lt;img alt="" src="img/Error.png" /&gt;
            &lt;/span&gt;&lt;span runat="server" id="lblError"&gt;&lt;/span&gt;
        &lt;/div&gt;
    &lt;/div&gt;
    &lt;asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional" RenderMode="Inline"&gt;
    &lt;Triggers&gt;
        &lt;asp:AsyncPostBackTrigger ControlID="drplstStd" /&gt;
    &lt;/Triggers&gt;
        &lt;ContentTemplate&gt;
            &lt;div class="actions"&gt;
                &lt;div class="left"&gt;
                    &lt;asp:Button ID="btnBack" runat="server" Text="Add new" Height="25px" OnClick="btnBack_Click" /&gt;
                    &lt;br /&gt;
                    &lt;br /&gt;
                    &lt;br /&gt;
                    &lt;asp:DropDownList ID="drplstStd" runat="server" AppendDataBoundItems="true" AutoPostBack="true"
                        onselectedindexchanged="drplstStd_SelectedIndexChanged"&gt;
                        &lt;asp:ListItem Selected="True" Text=" --Select Standard-- " Value="0"&gt;&lt;/asp:ListItem&gt;
                    &lt;/asp:DropDownList&gt;
                    &lt;br /&gt;
                     &lt;asp:DropDownList ID="drplstSem" runat="server"&gt;

                    &lt;/asp:DropDownList&gt;
                    &lt;br /&gt;
                    &lt;asp:DropDownList ID="drplstSubj" runat="server" AppendDataBoundItems="true"&gt;
                        &lt;asp:ListItem Selected="True" Text=" --Select Subject-- " Value="0"&gt;&lt;/asp:ListItem&gt;
                    &lt;/asp:DropDownList&gt;
                    &lt;asp:TextBox ID="txtChapterSearch" runat="server"&gt;&lt;/asp:TextBox&gt;
                    &lt;asp:Button ID="btnSearch" runat="server" Text="Search" Height="25px" OnClick="btnSearch_Click" /&gt;
                &lt;/div&gt;
            &lt;/div&gt;
            &lt;fieldset&gt;
                &lt;legend&gt;Chapter details &lt;/legend&gt;
                &lt;asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" OnRowCommand="GridView1_RowCommand"
                    AllowPaging="True" OnPageIndexChanging="GridView1_PageIndexChanging" PageSize="10"
                    CssClass="grid" CellPadding="3" BorderColor="#CCCCCC" BorderWidth="1px" BackColor="White"
                    BorderStyle="None"&gt;
                    &lt;RowStyle BackColor="#F6F6F6" ForeColor="#333333" /&gt;
                    &lt;Columns&gt;
                        &lt;asp:TemplateField HeaderText="Id" Visible="False"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:Label ID="Label1" runat="server" Text='&lt;%# Bind("ChapterID") %&gt;'&gt;&lt;/asp:Label&gt;
                            &lt;/ItemTemplate&gt;
                            &lt;HeaderStyle Width="30px" /&gt;
                        &lt;/asp:TemplateField&gt;
                        &lt;asp:TemplateField HeaderText="Standard"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:Label ID="Label2" runat="server" Text='&lt;%# Bind("Standard") %&gt;'&gt;&lt;/asp:Label&gt;
                            &lt;/ItemTemplate&gt;
                            &lt;HeaderStyle Height="50px" /&gt;
                            &lt;ItemStyle Height="25px" /&gt;
                        &lt;/asp:TemplateField&gt;
                        &lt;asp:TemplateField HeaderText="Semester"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:Label ID="Label3" runat="server" Text='&lt;%# Bind("Semester") %&gt;'&gt;&lt;/asp:Label&gt;
                            &lt;/ItemTemplate&gt;
                        &lt;/asp:TemplateField&gt;
                        &lt;asp:TemplateField HeaderText="Subject"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:Label ID="Label4" runat="server" Text='&lt;%# Bind("Subject") %&gt;'&gt;&lt;/asp:Label&gt;
                            &lt;/ItemTemplate&gt;
                        &lt;/asp:TemplateField&gt;
                        &lt;asp:TemplateField HeaderText="Chapter"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:Label ID="Label5" runat="server" Text='&lt;%# Bind("ChapterName") %&gt;'&gt;&lt;/asp:Label&gt;
                            &lt;/ItemTemplate&gt;
                        &lt;/asp:TemplateField&gt;
                        &lt;asp:TemplateField HeaderText="ShortForm"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:Label ID="Label6" runat="server" Text='&lt;%# Bind("ChapterSName") %&gt;'&gt;&lt;/asp:Label&gt;
                            &lt;/ItemTemplate&gt;
                        &lt;/asp:TemplateField&gt;
                        &lt;asp:TemplateField ShowHeader="False"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:LinkButton ID="LinkButton1" runat="server" CausesValidation="False" CommandArgument='&lt;%#((GridViewRow)Container).RowIndex%&gt;'
                                    Text="Edit" CommandName="EditDetails"&gt;&lt;/asp:LinkButton&gt;
                            &lt;/ItemTemplate&gt;
                            &lt;ItemStyle Width="100" /&gt;
                        &lt;/asp:TemplateField&gt;
                        &lt;asp:TemplateField ShowHeader="False"&gt;
                            &lt;ItemTemplate&gt;
                                &lt;asp:LinkButton ID="LinkButton2" runat="server" CausesValidation="False" CommandArgument='&lt;%#((GridViewRow)Container).RowIndex%&gt;'
                                    Text="Delete" CommandName="DeleteDetails" OnClientClick="if (!window.confirm('Are you sure you want to delete this item?')) return false;"&gt;&lt;/asp:LinkButton&gt;
                            &lt;/ItemTemplate&gt;
                            &lt;ItemStyle Width="100" /&gt;
                        &lt;/asp:TemplateField&gt;
                    &lt;/Columns&gt;
                    &lt;FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /&gt;
                    &lt;PagerStyle CssClass="rowheader" HorizontalAlign="Center" /&gt;
                    &lt;SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" /&gt;
                    &lt;HeaderStyle CssClass="rowheader" /&gt;
                    &lt;EditRowStyle BackColor="#999999" /&gt;
                    &lt;AlternatingRowStyle BackColor="#FDFDFD" ForeColor="#284775" /&gt;
                &lt;/asp:GridView&gt;
             &lt;legend&gt;
                    &lt;asp:ImageButton ID="btnDisplay" runat="server" ImageUrl="~/Admin/img/view_refresh.png"
                        Height="16px" Width="16px" OnClick="btnDisplay_Click" /&gt;
                    &lt;asp:Label ID="lblDisplay" runat="server" Text="Label"&gt;&lt;/asp:Label&gt;
                &lt;/legend&gt;
            &lt;/fieldset&gt;
        &lt;/ContentTemplate&gt;
    &lt;/asp:UpdatePanel&gt;
&lt;/asp:Content&gt;
</code></pre>
