Example JS game

game.html

<script type="text/javascript">
  var guess, answer, message;

  answer = Math.floor(Math.random() * 100) + 1;
  console.log(answer);
  guess = prompt("What do you choose? 1-100?");

  if (guess == answer) {
    message = "Good guess, you're right!";
  } else {
    message = "Good guess, but YOU ARE WRONG."
  }

  alert(message);
</script>