C#: Simple Console Menu

// Online post: https://pastebin.com/9NmGvV4y

// See my more advanced menu here: https://pastebin.com/K4KcHS5u

using System;
using System.Diagnostics;

namespace ConsoleMenu
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            var indent = " ";
            var outdent = Environment.NewLine + Environment.NewLine;

            var selectedIndex = 0;

            while (true)
            {
                Console.Clear();

                // Print a vertical menu.
                for (var i = 0; i < MENU_OPTIONS.Length; i++)
                {
                    var menuOption = MENU_OPTIONS[i];
                    WriteMenuEntry(menuOption, i == selectedIndex, indent, outdent);
                }

                // Print a dividing line.
                Console.WriteLine(new String('-', 80));

                // Print a horizontal menu.
                for (var i = 0; i < MENU_OPTIONS.Length; i++)
                {
                    var menuOption = MENU_OPTIONS[i];
                    WriteMenuEntry(menuOption, i == selectedIndex, indent);
                }

                Console.WriteLine();

                // Process input.
                var userInput = Console.ReadKey();
                switch (userInput.Key)
                {
                    case ConsoleKey.LeftArrow:
                    case ConsoleKey.UpArrow:
                        // Loop around backwards.
                        selectedIndex = (selectedIndex - 1 + MENU_OPTIONS.Length) % MENU_OPTIONS.Length;
                        break;

                    case ConsoleKey.RightArrow:
                    case ConsoleKey.DownArrow:
                        // Loop around forwards.
                        selectedIndex = (selectedIndex + 1) % MENU_OPTIONS.Length;
                        break;

                    case ConsoleKey.Enter:
                        ExecuteMenuEntry(selectedIndex);
                        break;

                    default:
                        Console.WriteLine($"\n{indent}The pressed key '{userInput.Key}' is not associated with a menu function.");
                        Pause();
                        break;
                }
            }
        }

        private static void WriteMenuEntry(string text, bool highlight, string indent = null, string outdent = null)
        {
            Console.Write(indent);

            if (highlight)
            {
                // Apply selected colors.
                Console.ForegroundColor = ConsoleColor.Black;
                Console.BackgroundColor = ConsoleColor.White;
            }

            Console.Write(text);

            if (highlight)
            {
                // Restore normal colors.
                Console.ForegroundColor = ConsoleColor.White;
                Console.BackgroundColor = ConsoleColor.Black;
            }

            Console.Write(outdent);
        }

        private static void ExecuteMenuEntry(int index)
        {
            // If exit option is selected.
            if (index == MENU_OPTIONS.Length - 1)
                Environment.Exit(0);

            Console.WriteLine($"\n  Selected index: {index}");
            Pause();
        }

        private static void Pause()
        {
            // Press any key to continue.
            if (Debugger.IsAttached == false)
            {
                Console.WriteLine();
                Console.Write("Press any key to continue . . . ");
                Console.ReadKey();
            }
        }

        private static readonly string[] MENU_OPTIONS = new string[] {
            " Option 1 ",
            " Option 2 ",
            " Option 3 ",
            " Exit ",
        };
    }
}