我的第一次循环中的条件似乎无法正常工作

Question

<script>
function Play() {
var guesses = 1
var number = 0
var points = 0
var cp = 0
var level = " "
var x = 0
while (level != "a" || "A" || "b" || "B" || "c" || "C" || "d" || "D"){
    level = prompt("Select Your Difficulty");
    if (level == "a" || "A" || "b" || "B" || "c" || "C" || "d" || "D") {
        if (level == "a" || level == "A") {
            x = 30;
        }
        else if (level == "b" || level == "B") {
            x = 50;
        }
        else if (level == "c" || level == "C") {
            x = 70;
        }
        else if (level == "d" || level == "D") {
            x = 100;
        }
    }
    else if (level != "a" || "A" || "b" || "B" || "c" || "C" || "d" || "D") {
        if (level == null) {
            return;
        }
        else {
            alert("You Went Sphagetti On Your Keyboard And Missed");
    }
    }
}
var answer = Math.floor(Math.random() * x) + 1;
number = prompt("What Is Your First Guess?");
if (number == null) {
    return;
}
//The Beginning Of The While Loop
while (guesses <= 4) {
    //Give The User A Point And Restart The Guesses
    //Generate A New Number For Them To Guess
    if (number == answer) {
        alert("You Guessed Correctly! You Get One Point!");
        alert("The Number Will Now Change, But Will Still Be Within 1-30");
        guesses = 1;
        points = points + 1;
        answer = Math.floor(Math.random() * x) + 1;
        number = prompt("What Is Your Guess For The New Number?");
        if (number == null){
            return;
        }
        //If The Number The User Guessed Equals The Answer
        //Go Back To The Start Of The Loop
        else if (number == answer) {
            continue;
        }
    }
    if (number < answer) {
        alert("Wrong! The Number Is To Low! NACHO CHEESE");
    }
    else if (number > answer) {
        alert("Wrong! The Number Is To High! YOU ARE SHELLFISH!");
    }
    number = prompt("You've Made " + guesses + " Guess(es)");
    if (number == null) {
        return;
    }
    if (number == answer) {
        continue;
    }
    else if (number != answer) {
        guesses = guesses + 1;
    }
}
//If The User Gets Wrong On All 5 Guesses
//Tell Them They Lost And Give Them The Answer
//Display Their Total Points
alert("You Have Guessed Incorrectly 5 Times. The Number Was " + answer);
cp = points.toString();
document.getElementById("points").innerHTML= "Point Streak: " + cp;
}
</script>-

您好，我想知道为什么我的第一个while循环中的条件似乎无法正常工作。当我输入一个应该突破循环的字母，因为条件是它不等于这些字母之一时，它最终会再次要求我（“选择你的难度”）。之前它还给了我“你的键盘上的意大利面并且错过了”）当我输入一封应该突破循环的信件时...如果我没有弄错，如果在那里甚至不应该进入其他如果我输入其中一个字母对吗？请指导我出错的地方。