ButtonImageExample.swift

private func setCloseButtonBackgroundImage() {
  closeButton.setImage(StyleKit.imageOfCloseButton(color: .closeButtonNormal), for: .normal)
  closeButton.setImage(StyleKit.imageOfCloseButton(color: .closeButtonHighlighted), for: .highlighted)
}

override func awakeFromNib() {
    super.awakeFromNib()
    setCloseButtonBackgroundImage()
}
 
 override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) { 
    super.traitCollectionDidChange(previousTraitCollection)
    if #available(iOS 13.0, *) {
        guard let prev = previousTraitCollection,
            traitCollection.userInterfaceStyle != prev.userInterfaceStyle else { return }
  
        setCloseButtonBackgroundImage()
    }
}