I have a in a user control. In that, I have added a HTML table in which there is a button. I need to have the buttons aligned to the bottom of the cell. I tried setting the property in the CSS file the style does not gets applied. What is it that I am doing wrong?

ASCX file:

<link href="CSSFile.css" rel="stylesheet" type="text/css" />
.
.
.
<td>
  <asp:Button ID="btnOK" runat="server" Text="OK" Width="66px" CssClass="ButtonClass"/>
  <asp:Button ID="btnClose" runat="server" Text="Close" Width="66px"/>
</td>

CSS File:

ButtonClass
{
  border: thin groove #000000;
  vertical-align: bottom;
  color: #000000;
  background-color: #99FFCC;
}

The CSS file and the user control reside in the same folder.