Simple palindrome checker

Palindrome.cs

namespace Palindrome
{
    class Program
    {
        static void Main(string[] args)
        {
            var palindromeChecker = new PalindromeCheckerImpl();
            Console.WriteLine(palindromeChecker.IsPalindrome("den laks skal ned"));
            Console.WriteLine(palindromeChecker.IsPalindrome("den laks skal ikke ned"));
        }
    }

    public interface IPalindromeChecker
    {
        bool IsPalindrome(string s);
    }

    public class PalindromeCheckerImpl : IPalindromeChecker
    {
        public bool IsPalindrome(string s)
        {
            if (s.Length < 2) return true;
            if (s.First() != s.Last()) return false;
            return IsPalindrome(s.Substring(1, s.Length - 2));
        }
    }
}