index.js

// Button
$(document).ready(function () {
    var $button = $('#button');
    var $form = $('#the-form');
    var $emailinput = $('#email');
    var $emaillabel = $('#email-label');
    var $submit = $('#submit-btn');

    $button.on('click', function (event) {
        $button.addClass('fadeOut');
    });

    $button.one('webkitAnimationEnd mozAnimationEnd MSAnimationEnd oanimationend animationend', function(){
       $button.addClass('hide');
       $form.removeClass('hide');
       $form.addClass('fadeIn');
    });
    $emailinput.on('focus', function (event) {
        $emaillabel.addClass('active');
    });
    $emailinput.on('blur', function (event) {
        if ($emailinput.val().trim() == "") {
            $emaillabel.removeClass('active');
        }
    });
    $emailinput.on('keyup', function (event) {
        if (event.target.value.length > 0) {
            $submit.removeClass('hide');
        }
        else {
            $submit.addClass('hide');
        }
    });
});