body img {
  width: 100%;
  height: 100%;
  position: fixed;
  top: 0;
  left: 0;
  z-index: -1;
}
.calculater {
  width: 500px;
  height: 500px;
  margin: 50px auto;
  padding: 20px;
  border-radius: 8px;
  background-image: linear-gradient(
    to right,
    #bfecff 0,
    #cdc1ff 33%,
    #fff6e3 66%,
    #ffccea 100%
  );
}
.top {
  display: grid;
  grid-template-columns: 15% 85%;
  gap: 10px;
  margin-bottom: 15px;
}
.screen {
  height: 70%;
  color: #000000;
  font-size: 3rem;
  text-align: right;
  padding: 5px;
  border-radius: 20px;
  overflow: hidden;
  border: 3px solid #000000;
}
#clear {
  width: 70px;
  height: 70px;
  background-color: #f95454;
  color: white;
  border-radius: 20px;
  font-size: 45px;
}
.keys {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.button {
  width: 100%;
  height: 90px;
  padding: 10px;
  font-size: 45px;
  background-color: #3a6d8c;
  color: white;
  border: none;
  border-radius: 30px;
  cursor: pointer;
  transition: background-color 0.2s;
}
.operators {
  background-color: #a64d79;
}
#clear:hover {
  background-color: #c62e2e;
}
.button:hover {
  background-color: #003161;
}
.operators:hover {
  background-color: #6a1e55;
}