body {
  background-color: #000000;
}

.calculator {
  width: 300px;
  border: 1px solid #ffffff;
  border-radius: 8px;
  margin: 50px auto;
  padding: 10px;
  background-color: #007396;
  box-shadow: 0px 19px 40px 22px rgba(255, 255, 255, 0.2);
}
#display {
  width: 95%;
  margin-bottom: 10px;
  padding: 10px;
  font-size: 20px;
  text-align: right;
  border: 2px solid black;
  color: black;
  box-shadow: inset 0px 11px 24px 22px rgba(0, 0, 0, 0.1);
}
.buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-gap: 5px;
}
.buttons button {
  padding: 10px;
  font-size: 18px;
  border-radius: 5px;
  border: 1px solid #ccc;
  background-color: #eee;
  cursor: pointer;
}
.buttons button:hover {
  background-color: #0259aa;
  border: 2px solid black;
  transform: scale(1.2);
}

.buttons button:active {
  transform: scale(0.95);
}