* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
  font-family: sans-serif;
}

body {
  width: 100%;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: linear-gradient(45deg, #0a0a0a, #3a4452);
}

.calculator {
  border: 1px solid #717377;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0px 3px 15px rgb(113, 115, 199, 0.5);
  background-color: transparent;
}

.calculator input {
  width: 220px;
  background-color: transparent;
  border: none;
  outline: none;
  margin: 10px;
  padding: 10px;
  box-shadow: 0px 3px 15px rgb(84, 84, 84, 0.1);
  font-size: 20px;
  text-align: right;
  color: wheat;
  font-weight: 600;
}

.calculator input::placeholder {
  color: white;
}
button {
  border: none;
  width: 40px;
  height: 40px;
  margin: 10px;
  border-radius: 50%;
  background-color: transparent;
  color: white;
  font-size: 15px;
  box-shadow: -8px -8px 15px rgb(255, 255, 255, 0.1);
  cursor: pointer;
}
.operator {
  color: chartreuse;
}