body {
  min-height: 100dvh; /* correct iPhone visible height */
  display: flex;
  justify-content: center;
  align-items: center;
  background: #fff;

  /* iPhone notch / bars safety */
  padding-top: env(safe-area-inset-top);
  padding-bottom: env(safe-area-inset-bottom);
}
.box{
  text-align: center;
  padding: 20px;
  max-width: 900px;
}