.calculator {
  max-width: 200px;
  margin: 0 auto;
  padding: 20px;
  text-align: center;
  background-color: #f2f2f2;
}

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

#display {
  width: 100%;
  margin-bottom: 10px;
  padding: 5px;
  font-size: 1.5rem;
  background-color: #f5f5f51d;
  border: none;
  text-align: right;
  overflow: hidden;
}

.buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-gap: 5px;
}

button {
  width: 100%;
  height: 40px;
  font-size: 1.2rem;
  border: none;
  border-radius: 5px;
  background-color: #f1f1f1;
  cursor: pointer;
}

.copyright {
  position: fixed;
  bottom: 0;
  width: 100%;
  text-align: center;
  padding: 10px;
  background: rgb(255, 255, 255);
  color: #000000;
}

.number {
  background-color: #ffffff;
  color: #333333;
}

.operator {
  background-color: #ffcc00;
  color: #ffffff;
}

.equals {
  background-color: #4caf50;
  color: #ffffff;
}

.clear {
  background-color: #e53935;
  color: #ffffff;
}

.backspace {
  background-color: #cccccc;
  color: #333333;
}