Illuminati Lock

using System;

class IlluminatiLock
{
    public static void Main ()
    {
        int input = int.Parse (Console.ReadLine ());
        int length = 3 * input;
        char eye = '#';
        char filler = '.';

        string sideBorder = new string (filler, input);
        string middleBorder = new string (eye, input);
        Console.WriteLine ("{0}{1}{0}", sideBorder, middleBorder);

        for (int i = 1; i <= input/2; i++) {
            int sideSpace = input - 2 * i;
            int centerSpace = input - 2;
            int middleSpace = (length - 2 * sideSpace - centerSpace - 6) / 2;
            string side = new string (filler, sideSpace);
            string center = new string (filler, centerSpace);
            string middle = new string (filler, middleSpace);

            Console.WriteLine ("{0}##{1}#{2}#{1}##{0}", side, middle, center);
        }

        for (int i = input/2; i >0; i--) {
            int sideSpace = input - 2 * i;
            int centerSpace = input - 2;
            int middleSpace = (length - 2 * sideSpace - centerSpace - 6) / 2;
            string side = new string (filler, sideSpace);
            string center = new string (filler, centerSpace);
            string middle = new string (filler, middleSpace);

            Console.WriteLine ("{0}##{1}#{2}#{1}##{0}", side, middle, center);
        }

        Console.WriteLine ("{0}{1}{0}", sideBorder, middleBorder);

    }
}