This part is written in English.
const button = document.querySelector('input');
const paragraph = document.querySelector('p');
button.addEventListener('click', updateButton);
var phone = document.getElementById("phone");
phone.addEventListener('focus', phoneMask);
function phoneMask() {
var num = $(this).val().replace(/\D/g,'');
$(this).val(num.substring(0,1) + '(' + num.substring(1,4) + ')' + num.substring(4,7) + '-' + num.substring(7,11));
}