body {
  background-color: #000;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, sans-serif;
}

.calculator {
  width: 320px;
  background-color: #000;
  border-radius: 40px;
  padding: 20px;
  box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}


.display {
  background-color: #000;
  color: white;
  font-size: 32px;
  text-align: right;
  padding: 20px;
  border-radius: 10px;
  box-sizing: border-box;
  height: 120px;
  /* overflow-y: auto;         Enables vertical scrolling */
  overflow-x: hidden;
  display: flex;
  /* flex-direction: column;   Stack lines vertically */
  justify-content: flex-end;
  word-wrap: break-word;
  line-height: 1.4;
}



.buttons {
  margin-top: 10px;
}

.row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 10px;
}

.btn {
  width: 70px;
  height: 70px;
  font-size: 28px;
  border: none;
  border-radius: 50%;
  cursor: default;
  color: white;
}

.btn:active {
  opacity: 0.7;
}

.gray {
  background-color: #a5a5a5;
  color: black;
}

.orange {
  background-color: #ff9500;
}

.dark {
  background-color: #333333;
}

.zero {
  width: 150px;
  border-radius: 35px;
  text-align: left;
  padding-left: 28px;
}