body {
  background: #1f2833;
  color: #fff;
  font-family: "Rubik", sans-serif;
}

.container {
  max-width: 700px;
  margin: auto;
}

h1 {
  text-align: left;
  font-size: 3em;
  font-weight: 300;
}

h2 {
  margin: 0;
  font-weight: 400;
}

div#display {
  text-align: right;
  /* border: 1px solid #000; */
  padding: 40px 24px;
  box-sizing: border-box;
  border-radius: 12px;
  background: rgba(0, 0, 0, 0.4);
  margin-bottom: 8px;
  font-size: 3em;
}

.calculator-btn-container {
  display: flex;
}

.num-pad {
  width: 80%;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 12px;
  padding: 16px;
  margin-right: 16px;
}

.operation-pad {
  width: 20%;
  display: flex;
  flex-direction: column;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 12px;
  padding: 16px;
}

.num-pad ul {
  margin: 0;
  padding: 0;
  gap: 8px;
  height: 100%;
}

.num-pad ul,
.operation-pad ul {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  list-style-type: none;
}

.num-pad ul li,
.operation-pad ul li {
  padding: 1em 2em;
  cursor: pointer;
  border-radius: 8px;
}

.num-pad ul li {
  background: rgb(115 191 113);
  /* background-color: #2776EA; */
  font-size: 1.4em;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: 0.2s all ease-in-out;
}

.num-pad ul li:hover {
  color: rgb(115 191 113);
  background: #fff;
}

.num-pad ul li:nth-child(1) {
  grid-row-end: 5;
}

.operation-pad button {
  background-color: #e84a5f;
  background-color: #fe755e;
  border: none;
  height: 100%;
  margin-bottom: 8px;
  padding: 20px;
  border-radius: 8px;
  color: #fff;
  font-size: 2em;
  text-align: center;
  cursor: pointer;
  transition: 0.2s all ease-in-out;
}

.operation-pad button:hover {
  background-color: #fff;
  color: #fe755e;
}

.btn-clicked {
  transform: scale(0.5);
}

button#equals-btn {
  margin-bottom: 0;
}

#clear-btn {
  grid-column: span 1;
  border-radius: 8px;
  font-size: 1.2em;
  border: none;
  cursor: pointer;
  font-family: "Rubik", sans-serif;
  color: #2776ea;
  transition: 0.2s all ease-in-out;
}

#clear-btn:hover {
  background: #2776ea;
  color: #fff;
}

.alert {
  display: none;
  color: #ff5757;
  font-size: 0.9rem;
  font-weight: 200;
}

.alert p {
  margin-top: 0;
  margin-bottom: 0;
}

.show-alert {
  display: block;
}