Ideas for implementing static method pop-up dialog box

/// <summary>
/// The pop-up of a JavaScript window is actually a DIV defined
/// </summary>
/// <param name="js">Window information</param>
public static void Alert(string message)
{
message = "<div style='border:darkturquoise 1px solid; width:200px;color: blue; font-style: normal; font-family: Kaiyi_GB2312;height:auto; background-color: #f4f8ff;padding:15px 0px; text-align:center; font-size: 23px;left: 360px; position: absolute; top: 200px;'>" + message + "</div>";
(message);
}