body {
  background-color: rgb(213, 255, 246);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

div {
  background-color: white;
  flex: 1;
}

#container {
  display: flex;
  flex-direction: column;
  width: 500px;
  height: 500px;
}

.btn-container {
  border: 1px solid black;
  background-color: rgb(255, 255, 255);
  font-size: 50px;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 20px;
  padding: 10px;
}

button {
  min-width: 100px;
  font-size: 50px;
}

.row {
  display: flex;
}

.filled-in {
  background-color: black;
}

.switch {
  position: relative;
  display: inline-block;
  width: 60px;
  height: 34px;
}

/* Hide default HTML checkbox */
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

/* The slider */
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #ccc;
  -webkit-transition: 0.4s;
  transition: 0.4s;
}

.slider:before {
  position: absolute;
  content: "";
  height: 26px;
  width: 26px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  -webkit-transition: 0.4s;
  transition: 0.4s;
}

input:checked + .slider {
  background-color: #2196f3;
}

input:focus + .slider {
  box-shadow: 0 0 1px #2196f3;
}

input:checked + .slider:before {
  -webkit-transform: translateX(26px);
  -ms-transform: translateX(26px);
  transform: translateX(26px);
}

/* Rounded sliders */
.slider.round {
  border-radius: 34px;
}

.slider.round:before {
  border-radius: 50%;
}