@import url("https://fonts.googleapis.com/css2?family=Roboto&display=swap");
html,
body {
  height: 100%;
  width: 100%;
  font-family: "Roboto", sans-serif;
}

.button {
  padding: 20px;
  margin: 0 3px;
  width: 55px;
  border: 2px solid black;
  border-radius: 9px;
  cursor: pointer;
}
.row {
  margin: 8px 0;
}
.row input {
  margin: 0;
  padding: 15px 5px;
  border: 2px solid black;
  border-radius: 9px;
  font-size: 20px;
}

#display {
  text-align: right;
}