.popup-footer {
  font-size: 1rem;
  position: fixed;
  -webkit-transition: 0.3s;
  -o-transition: 0.3s;
  transition: 0.3s;
  bottom: -900px;
  width: 100%;
  padding: 1rem 0;
  box-shadow: 0 0 1rem rgba(0, 0, 0, 0.1);
  background-color: #fff;
  z-index: 2;
}

.popup-footer_displaied {
  bottom: 0;
}

@media all and (max-width: 575px){
  .popup-footer {
    font-size: .875rem;
  }
}