@media (width >= 1000px) {
  fieldset, fieldset > div {
    width: 100%;
  }

  #double {
    width: 95%;
    display: inline-grid;
    column-gap: 2em;
    grid-template-columns: repeat(2, calc(50% - 1em));
  }
}

iframe, input, textarea {
  width: 100%;
}

iframe {
  height: 100vh;
  border: none;
}