function validate_digits() {
	var pi_game = document.getElementById("pi_game");
	var correct = "3.141592653589793238462643383279502884197169399375105820974944592";
	var input_length = pi_game.value.length;

	if(pi_game.value == correct.substring(0,input_length)) {
		pi_game.style.border = "2px solid #11CC11";

		if(pi_game.value.length == 65) {
			pi_game.disabled = "true";
			alert("Gratulerer! Du klarte å huske hele adressen");
		}
	} else {
		pi_game.style.border = "2px solid #CC1111";
	}

}