getValue gets the string the user entered. Removes characters, numbers, and spaces.

______________________________________

reverseString reverses it.

______________________________________

displayString displays the palindrome.

//Get the value from the string
function getValue() {
document.getElementById("alert-success").classList.add("invisible")
document.getElementById("alert-fail").classList.add("invisible")

let userString = document.getElementById("userString").value

userString = userString.toLowerCase()

// Remove non alphanumeric characters and numbers
userString = userString.replace(/[^a-z]/gi, '')

let reversedString = reverseString(userString)

let isPalindrome = false

if (userString == reversedString) {
isPalindrome = true
}

displayString(reversedString, isPalindrome)
}

//Reverse the string
function reverseString(userString) {
let revString = []

for (let i = userString.length - 1; i >= 0; i--) {
revString += userString[i]
}

return revString
}

//Display the message with the reversed string
function displayString(revString, isPalindrome) {
if (isPalindrome == true) {
document.getElementById("msg-success").innerHTML = `${revString}`
document.getElementById("alert-success").classList.remove("invisible")
} else {
document.getElementById("msg-fail").innerHTML = `${revString}`
document.getElementById("alert-fail").classList.remove("invisible")
}
}