body {
  font-size: 64px;
  background-color: black;
}

.container {
  display: grid;
  justify-content: center;
  grid-template-columns: 80px 80px 80px 80px;
  grid-template-rows: 80px 80px;
  grid-template-areas: "header header header header" "main main main main" "main main main main" "main main main main" "main main main main" "main main main main";
}

.calculatorDisplay {
  grid-area: header;
  color: white;
  text-align: right;
  padding-right: 21px;
}

#globalAnswer {
  background-color: green;
  grid-column-start: 1;
  grid-column-end: span 2;
  font-size: 36px;
}

#currentValue {
  background-color: blue;
  grid-column-start: 3;
  grid-column-end: span 2;
  text-align: right;
}

.btn {
  background-color: dimgray;
  border: none;
  color: white;
  padding: 20px;
  text-align: center;
  margin: 4px 2px;
  border-radius: 50%;
}

.orange {
  background-color: orange;
}

button.orange:focus {
  background-color: white;
  color: gold
}

.silver {
  background-color: silver;
  color: black;
}

button.silver:focus {
  background-color: white;
  color: black
}

.equals {
  background-color: orange;
}

button.equals:focus {
  background-color: white;
  color: gold
}

.zero {
  grid-row: 6;
  grid-column-start: 1;
  grid-column-end: span 2;
  border-radius: 40px / 35px;
}

button {
  font-size: 26px;
}