* {
  box-sizing: border-box;
  font-family: Arial, sans-serif;
}

body {
  background: #4f8cc9;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.calculator {
  background: #eaf4ff;
  padding: 20px;
  border-radius: 20px;
  width: 320px;
}

.display {
  background: #cfe7ff;
  padding: 15px;
  border-radius: 12px;
  margin-bottom: 15px;
}

#expression {
  font-size: 14px;
  color: #3b6ea5;
}

#result {
  font-size: 36px;
  text-align: right;
  color: #0f2f52;
}

.buttons {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 10px;
}

button {
  padding: 14px;
  border: none;
  border-radius: 12px;
  background: #cfe7ff;
  font-size: 16px;
  cursor: pointer;
}

button:hover {
  background: #b6dcff;
}

.enter {
  grid-column: span 2;
  background: #4f8cc9;
  color: white;
}