.calculator select {
  display: block;
  width: 100%;
  border: 0;
  border-bottom: 1px solid #aeb8c4;
  padding: 10px 2px 12px;
  margin-top: 7px;
  background: transparent;
  border-radius: 0;
  color: #162437;
  font: 16px Arial, sans-serif;
}

.calculator .full {
  grid-column: 1 / -1;
}

@media (max-width: 600px) {
  .calculator .full {
    grid-column: 1;
  }
}