how to highlight a link button when it is clicked?

Hello Mate!,

          I have a link button .And All i need is to make that link button be highlighted when it is clicked.

         Some thing like a:selected in the style sheet

currently my code

<asp:LinkButton ID="a1" runat="server" OnClick="clientsort">A</asp:LinkButton>

like the above i have link buttons for other letters from B to Z.

And i alredy have a method which will fire when the link button is clicked

Thanks in advance!,
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