.modal {
  display: none;
  display: grid;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  position: fixed;
  left: 0;
  top: 0;
  z-index: 99998;
  overflow-y: auto;
  visibility: hidden;
  opacity: 0;
}

.modal.open {
  display: block;
}

.modal.open .modal__box {
  -webkit-transform: scale(1);
      -ms-transform: scale(1);
          transform: scale(1);
}