JSFiddle - React, Tailwind, and code Playground

JavaScript

var playagain = "Y";

while (playagain == "Y") {
    var userChoice = prompt("Choose rock, paper, or scissors");
    var computerChoice = Math.random();

    if (computerChoice < 0.34) {
        computerChoice = "rock";
    } else if (computerChoice <= 0.67) {
        computerChoice = "paper";
    } else {
        computerChoice = "scissors";
    }

    function compare(choice1, choice2) {

        if (choice1 == choice2) {
            return ("It's a tie!");
        }
        if (choice1 == "rock") {
            if (choice2 == "scissors") {
                return ("You win!");

            } else {
                return ("computer wins!");
            }
        }
        if (choice1 == "paper") {
            if (choice2 == "rock") {
                return ("you win!");
            } else {
                return ("computer wins!");
            }
        }
        if (choice1 == "scissors") {
            if (choice2 == "rock") {
                return ("computer wins!");
            } else {
                return ("you win!");
            }
        }
    }

    document.body.innerHTML += compare(userChoice, computerChoice) + "<br/>";
    playagain = prompt("Do you want to play again, Y or N");
}