.footer-popup {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 10000;
}

.footer-popup__overlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.6);
}

.footer-popup__content {
  position: relative;
  max-width: 420px;
  width: 90%;
  margin: auto;
  top: 50%;
  transform: translateY(-50%);
  background: #fff;
  padding: 24px;
  border-radius: 8px;
  text-align: center;
}