using System;

public class Program

{

    public static void Main()

    {

        var aux = Base64Encode("VJgPOTjljXeyM4u4V4etX695_pQa:rEzFkq3hVchgEnel6m2FnL2_JdMa");

        Console.WriteLine(aux);

    }

    public static string Base64Encode(string plainText) 

    {

         var plainTextBytes = System.Text.Encoding.UTF8.GetBytes(plainText);

         return System.Convert.ToBase64String(plainTextBytes);

    }

}