Jquery countdown warn user 5 minutes before time over

i want to know how to show alert model pop up when user do nothing in web editor 5 min before

i am trying through web config

please help-

Session Idle: seconds.

Your Session will expire in seconds.

Do you want to reset?

rel="stylesheet" type="text/css" />

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Response.Cache.SetCacheability(HttpCacheability.NoCache);

if (!this.IsPostBack)

{

Session["Reset"] = true;

Configuration config = WebConfigurationManager.OpenWebConfiguration("~/Web.Config");

SessionStateSection section = (SessionStateSection)config.GetSection("system.web/sessionState");

int timeout = (int)section.Timeout.TotalMinutes * 1000 * 60;

ClientScript.RegisterStartupScript(this.GetType(), "SessionAlert", "SessionExpireAlert(" + timeout + ");", true);

}

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