simple-modal for once run

modal.html

<style type="text/css">
  .gaye-modal--modal {
    width: 100%;
    height: 100%;

    position: fixed;
    top: 0; left: 0;
    z-index: 9999;

    background-color: rgba(0, 0, 0, 0.5);
  }

  .gaye-modal--body {
    width: 100%;
    max-width: 600px;
    max-height: 600px;
    display: block;

    position: absolute;
    top: 0; left: 0;
    bottom: 0; right: 0;
    margin: auto;

    border-radius: 3px;
    overflow: hidden;
    box-shadow: 0 0 15px 0 rgba(0, 0, 0, 0.7);
  }

  .gaye-modal--close {
    display: block;
    width: 80px; height: 30px;

    position: absolute;
    top: 10px; right: 10px;

    border-radius: 3px;
    box-sizing: border-box;

    background-color: black;
    color: white;

    font-size: 12px;
    font-weight: bold;
  }

  .gaye-modal--body img {
    max-width: 100%;
    display: block;
  }
</style>
<script>
  function modal () {
    var wrapper = document.createElement('div');
    wrapper.classList.add('gaye-modal--modal');

    var modal = document.createElement('div');
    modal.classList.add('gaye-modal--body');

    var invitation = new Image();
    invitation.src = 'images/invitation.png';
    invitation.alt = 'Davetiye';

    var close = document.createElement('button');
    close.classList.add('gaye-modal--close');
    close.textContent = 'Kapat';

    modal.appendChild(invitation);
    modal.appendChild(close);
    wrapper.appendChild(modal);

    (document.body).appendChild(wrapper);

    localStorage.setItem('gaye-modal', true);

    setTimeout(function () {
      document.querySelector('.gaye-modal--close').addEventListener('click', event => {
        document.querySelector('.gaye-modal--modal').remove();
        localStorage.setItem('gaye-modal', false);
      });
    }, 500);
  }

  var modalKey = localStorage.getItem('gaye-modal');

  if (!modalKey && modalKey != true) {
    modal();
  } else {
    console.log('modal has been closed already!');
  }
</script>