Styling Listview in asp.net - css

Question

I have got a listview which is styled with css but dosent work.Am I missing something here.
<asp:ListView ID="msg_list" runat="server">
<ItemTemplate>
<tr class="myitem">
<td> <asp:Label role="menuitem" ID="msg_lbl" runat="server" text='<%#Eval("msg")%>' /> </td>
</tr>
<%--<hr style=" margin-top:1px; margin-bottom:1px; " />--%>
</ItemTemplate>
</asp:ListView>
Here is the css
.myitem
{
background-color:Red;
}

Answer 1

Table rows (tr) can't be styled as other elements (e.g. table cells (td)), meaning they don't react on every kind of styling. Why don't you just write:
Fiddle
<asp:ListView ID="msg_list" runat="server">
<ItemTemplate>
<table>
<tr class="myitem">
<td>
<asp:Label role="menuitem" ID="msg_lbl" runat="server" text='<%#Eval("msg")%>' />
</td>
</tr>
</table>
<%--<hr style=" margin-top:1px; margin-bottom:1px; " />--%></ItemTemplate>
</asp:ListView>
tr.myitem td{
width:200px;
height:20px;
border:2px solid;
background:red;
}
OR
Fiddle
<asp:ListView ID="msg_list" runat="server">
<ItemTemplate>
<table>
<tr class="myitem">
<td>
<asp:Label role="menuitem" ID="msg_lbl" runat="server" text='<%#Eval("msg")%>' />
</td>
</tr>
</table>
<%--<hr style=" margin-top:1px; margin-bottom:1px; " />--%></ItemTemplate>
.myitem {
background:red;
}
EDIT
You need to add <table> tag