change color of extra characters in UITextField - ios

Question

How can I change the color only of extra letters when typing in UITextField in Swift and return the color back when deleting?
I was able only to change color of all letters, when exceeding the limit
class ViewController: UIViewController, UITextFieldDelegate {
#IBOutlet weak var inputLimitField: UITextField!
#IBOutlet weak var characterCountLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
characterCountLabel.text = "10/10"
inputLimitField.delegate = self
}
func checkRemainingChars() {
let allowedChars = 10
let charsInTextView = -(inputLimitField.text?.count ?? 0)
let remainingChars = allowedChars + charsInTextView
characterCountLabel.textColor = .black
inputLimitField.textColor = .black
inputLimitField.layer.borderColor = UIColor.systemGray3.cgColor
if remainingChars < 0 {
characterCountLabel.textColor = .red
inputLimitField.textColor = .red
inputLimitField.layer.borderColor = UIColor.red.cgColor
inputLimitField.layer.cornerRadius = 6.0
inputLimitField.layer.borderWidth = 1.0
}
characterCountLabel.text = ("\(String(remainingChars))/10")
}
func textFieldDidChangeSelection(_ textField: UITextField) {
checkRemainingChars()
}
}
this is what I expected to get
enter image description here
and this is what I really get enter image description here
p.s. also I can't put a letter counter in the corner through TF's border, because there is a mistake when I import Material Components: No such module 'MaterialComponents'