*,
*::before,
*::after {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
  font-family: monospace;
  font-size: 26px;
  font-weight: bold;
}

.container {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.calculator {
  border: 2px solid black;
  border-radius: 5px;
  width: 500px;
  height: 600px;
  background-color: rgb(67, 66, 66);
  display: flex;
  flex-direction: column;
  padding: 5px;
  gap: 3px;
}

.calculator > div {
  flex: 1;
}

.display {
  background-color: gray;
  border: 4px solid black;
  display: flex;
  justify-content: end;
  align-items: center;
  font-size: 70px;
  font-weight: bolder;
  overflow: hidden;
  padding-right: 10px;
  white-space: nowrap;
}

.first,
.second,
.third,
.fourth,
.fifth {
  display: flex;
  gap: 3px;
}

.first > div,
.second > div,
.third > div,
.fourth > div,
.fifth > div {
  display: flex;
  justify-content: center;
  align-items: center;
  flex: 1;
  border: 2px solid black;
  border-radius: 5px;
  transition: background-color;
}

.first > div {
  background-color: #1e90ff;
}
.first > div:last-of-type,
.second > div:last-of-type,
.third > div:last-of-type,
.fourth > div:last-of-type,
.fifth > div:last-of-type {
  background-color: #ff8f1f;
}
.second > div,
.third > div,
.fourth > div,
.fifth > div {
  background-color: #217c7e;
}
.fifth > div:first-of-type {
  flex: 2;
}

.pressed {
  background-color: #d3d3d3 !important;
}