one_day

function parallax(){
  var scrolled = $(window).scrollTop();
  scrolled *= 0.2;
  if(scrolled > 400) return;
  $('#lk-conteyner').css('background-position','0 '+scrolled+'px');
}

if (this.value.length >= 3) {
    $(this).next('.btn-ok, .btn-last').removeClass('disabled');
    $(this).siblings('.valid-msg').css('display', 'none');
}

var new3lsg = localStorage.getItem('new3ls') || <ваше значение по умолчанию>;

<div id="foo" class="tg-grid-holder tg-layout-masonry">

const str = 'tg-grid-holder tg-layout-masonry';

setInterval(function() {
  var el = document.querySelector("#foo");
  var sel = el.getAttribute("class");

  if (str !== sel) {
    alert('oops!');
  }
}, 1000);