.form-grid{
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}
.form-grid .full{ grid-column: 1 / -1; }
@media (max-width: 820px){
  .form-grid{ grid-template-columns: 1fr; }
  .form-grid .full{ grid-column:auto; }
}