text: let input = prompt('enter the word "yes", upper or lower case');
  
  let reaction = '';
  if (input === null) {
    reaction = ':(';
  } else if (input.toLowerCase() === 'yes') {
    reaction = input + '!';
  } else {
    reaction = 'baaaaad: ' + input;
  }
  
  alert(reaction);
  