How can I separate the emoji only when the result is correct?
A random number that I type will show the same result with emojis. But, I only need the emoji when the result is correct. 
Only the emoji will appear when the answer is correct.
looks like a scope issue.
document.getElementById('displayStar').innerHTML =...
should be inside the else condition, now it's showing both message and 'displayStar' regardless the condition because it's outside of the scope, this part of code will run anyway.