How to toggle the class of elements in sequence?

Question

I am trying to have the class of each elements change one at a time in sequence automatically. This means element 1 glows then goes off as element 2 glows and then goes off and so on. When each element has glowed once the whole sequence starts over.

$('header div:first').toggleClass('highlight').nextAll().toggleClass('none');

function highlight() {
  var $off = $('header div.highlight').toggleClass('none');

  if ($off.next().length) {
    $off.next().toggleClass('none');
  } else {
    $off.prevAll().last().toggleClass('highlight');
  }
}

$(document).ready(function() {
  setInterval(highlight, 1000);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<header>
 <div>element 1</div>
 <div>element 2</div>
 <div>element 3</div>
 <div>element 4</div>
</header>

It wont work as expected (elements 2 through 4 highlight all at the same time and then go off while element 1 doesnt change at all) and I dont know why. What am I doing wrong?

Answer 1

So yes, you don't need the .none. Simply use your default styles and the .highlight class.
Get the number of items, create a counter, increment it and loop it using % Reminder Operator:

jQuery(function( $ ) { // DOM is ready

  var $el = $("header>div"), tot = $el.length, c = 0;

  $el.eq(c).addClass("highlight"); // initial highlight

  setInterval(function() {
    $el.removeClass("highlight").eq(++c%tot).addClass("highlight");
  }, 1000);

});

header > div           { transition:0.5s; -webkit-transition:0.5s; }
header > div.highlight { color:#f0f; }

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<header>
 <div>element 1</div>
 <div>element 2</div>
 <div>element 3</div>
 <div>element 4</div>
</header>

Some docs:
https://api.jquery.com/eq/
https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators#Remainder_()