I am trying to make a form with Materialize that validates one email. I start off with a submit button toggled to disabled. Ideally, when the email is filled in and validated, the submit button will stop being disabled and the user can click it to the next page. Here is my HTML:

```
<form id="survey">

        <div class="input-group">
            <p class="input-header">Enter Your Email</p>
            <div class="input-block input-field">
        <input id="email" type="text" name= "email" class="validate" required="" aria-required="true">
        <label for="email">Email Address</label>
      </div>
      <br></br>

        <a class="waves-light btn red lighten-2 disabled" id="submit">Submit
        <i class="material-icons right">send</i>
        </a>
        <br></br>
        <br></br>
        <br></br>

</form>

```

Here is the JavaScript/jQuery:

```
$(document).ready(function(){
  $('.parallax').parallax();

$('body').on('click', '#submit', function() {
let decision = confirm('Are you sure you would like to submit your survey?');
if (decision) {
  $.post('insert.php', $('#survey').serialize());
 window.location.href = 'thankyou.php';
}
});

$('body').on('click', 'input', function() {
checkValidity($(this));
});
$('body').on('focusout', 'input', function() {
checkValidity($(this));
});

function checkValidity (current) {
let isValid = true;
if (!current.val()) {
  isValid = false;
} else {
  isValid = iteratatingForm(current);
}
const submit = $('#submit');
if (isValid) {
  submit.removeClass('disabled');
} else {
  if (!submit.hasClass('disabled')) {
    submit.addClass('disabled');
  }
}
}

function iteratatingForm (current) {
if (!document.forms['survey']['email'].value) return false;
return true;
}});

```

Please let me know what I'm doing wrong! Thanks!