body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  background-color: white;
}

#calculator {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 300px;
  background-color: black;
  border-radius: 20px;
  padding: 1em;
  gap: 1em;
}

#display {
  width: 100%;
  height: 70px;
  background-color: black;
  color: white;
  font-size: 2.2em;
  text-align: right;
  padding: 0.4em 0.8em;
  margin-bottom: 10px;
  border-radius: 12px;
  box-shadow: inset 0 -2px 4px rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: flex-end;
  overflow: hidden;
  box-sizing: border-box;
}

.mainRow {
  display: flex;
  width: 100%;
  gap: 1em;
}

.mainRow button {
  flex: 1;
  height: 50px;
  font-size: 1.2em;
  border: none;
  border-radius: 8px;
  background-color: #a5a5a5;
  color: white;
  font-weight: bold;
  cursor: pointer;
}

.rows {
  display: flex;
  justify-content: space-between;
  width: 100%;
}

.rows button {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  font-size: 1.2em;
  border: none;
  cursor: pointer;
  font-weight: bold;
  transition: background-color 0.2s;
  color: white;
}

.rows
  button:not(.divide):not(.multiply):not(.subtract):not(.addition):not(.equal) {
  background-color: #333;
}

.divide,
.multiply,
.subtract,
.addition,
.equal {
  background-color: #f9a825;
  color: white;
}

.rows button:hover,
.mainRow button:hover {
  filter: brightness(1.1);
}