Hi,
Please see the following sample
<%@ Page Language="C#" %>
<%@ Register Assembly="Coolite.Ext.Web" Namespace="Coolite.Ext.Web" TagPrefix="ext" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title></title>
<style type="text/css">
.red .x-form-group-header-text {
color: red !important;
}
</style>
</head>
<body>
<form id="form1" runat="server">
<ext:ScriptManager ID="ScriptManager1" runat="server" />
<ext:Panel ID="Panel1" runat="server" Cls="red" Title="Subscription Details" Height="100" Width="300" FormGroup="true">
<Buttons>
<ext:Button runat="server" Text="Red" Pressed="true" ToggleGroup="color" EnableToggle="true">
<Listeners>
<Toggle Handler="if(pressed){#{Panel1}.addClass('red')}" />
</Listeners>
</ext:Button>
<ext:Button runat="server" Text="Normal" ToggleGroup="color" EnableToggle="true">
<Listeners>
<Toggle Handler="if(pressed){#{Panel1}.removeClass('red')}" />
</Listeners>
</ext:Button>
</Buttons>
</ext:Panel>
</form>
</body>
</html>
