body {
  height: 100vh;
  margin: 0;
  padding: 0;
  font-family: "WDXL Lubrifont TC", sans-serif;
  background-image: url(/assets/img/calculatorbg.png);
  background-size: cover;
  background-repeat: no-repeat;
  display: flex;
  justify-content: center;
  align-items: center;
}

.container {
  text-align: center;
  background-color: #4b1f011a;
  padding: 20px;
  border-radius: 20px;
  border: 1px solid black;
}

.display {
  font-size: 2rem;
  background-color: #551d021a;
  padding: 5px 12px;
  border-radius: 10px;
  margin-bottom: 15px;
  color: #422601;
  justify-content: end;
  display: flex;
  border: 2px solid #572707;
}

.buttons {
  display: grid;
  grid-template-columns: repeat(4, 63px);
  grid-auto-rows: 60px;
  gap: 11px;
  justify-content: center;
  margin-top: 20px;
  position: relative;
}

.btn {
  font-family: "WDXL Lubrifont TC", sans-serif;
  font-size: 1.2rem;
  border: 2px solid #572707;
  border-radius: 30%;
  background-color: #7235196e;
  color: #422601;
  cursor: pointer;
  transition: background-color 0.3s ease;
  transition: box-shadow 0.1s ease;
}

.btn:hover {
  background-color: #8840289a;
}

.btn:active{
  box-shadow:#cea883 3px 3px 6px 0px inset, rgba(63, 20, 0, 0.5) -3px -3px 6px 1px inset;
}

.equal {
  grid-row: span 2;
  background-color: #80200894;
  color: white;
  font-weight: bold;
  font-size: 1.2rem;
  border-radius: 10px;
}

.equal:hover {
  background-color: #701c0794;
}

.history {
  font-size: 1.3rem;
}

/* panel */
.history-panel {
  position: fixed;
  background-color: #c78f6a85;
  color: white;
  border: 2px solid #572707;
  border-radius: 15px;
  z-index: 1000;
  transition: all 0.4s ease;
  padding: 15px;
  max-height: 200px;
  overflow-y: auto;
  font-weight: 400;
  color:  #422601;
  margin: 6px;
  padding-bottom: 20px;
}

@media (min-width: 769px) {
  .history-panel {
    top: 50%;
    right: -260px;
    transform: translateY(-50%);
    width: 220px;
     max-height: 150px;
  }

  .history-panel.show {
    right: 90px;
  }
}

@media (max-width: 768px) {
  .history-panel {
    bottom: -400px;
    left: 5%;
    right: 5%;
    width: auto;
    transform: none;
    border-radius: 20px;
     max-height: 150px;
  }

  .history-panel.show {
    bottom: 0;
  }
}