.wrapper{
  /* width: 100%; */
  background-color: #222222;
  border-radius: 10px;
  padding: 25px 35px;
  margin-bottom: 30px;
}

.wrapper header{
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: #38ff8b;
}

.wrapper header h2{
  font-size: 1.6rem;
}

.wrapper header .column{
  display: flex;
  align-items: center;
}

.wrapper header .column span{
  font-weight: 500;
  margin-right: 15px;
  font-size: 1.19rem;
}

.volume-slider input{
  accent-color: #fff;
}

.keys-checkbox input{
  width: 60px;
  height: 30px;
  appearance: none;
  background-color: #4b4b4b;
  border-radius: 30px;
  cursor: pointer;
  position: relative;
  outline: none;
}

.keys-checkbox input::before{
  content: '';
  width: 20px;
  height: 20px;
  border-radius: 20px;
  position: absolute;
  top:50%;
  left: 5px;
  transform: translateY(-50%);
  background-color: #8c8c8c;
  transition: all 0.3s ease;
}

.keys-checkbox input:checked::before{
  left:35px;
  background-color: #fff;
}

.piano-keys {
  display: flex;
  margin-top: 25px;
}

.piano-keys .key{
  list-style: none;
  color: #28a745;
  text-transform: uppercase;
  cursor: pointer;
  position: relative;
  user-select: none;
}

.piano-keys .white{
  width: 70px;
  height: 230px;
  border-radius:8px;
  background: linear-gradient(#fff 96%, #eee 4%);
  border: 1px solid #000;
}

.piano-keys .white.active, .piano-keys .white:active{
  box-shadow: inset -5px 5px 20px rgba(0,0,0,0.2);
  background: linear-gradient(to bottom, #fff 0%, #eee 100%);;
}

.piano-keys .black{
  width: 44px;
  height: 140px;
  z-index: 2;
  margin: 0 -22px;
  border-radius: 0 0 5px 5px;
  background: linear-gradient(#333 96%, #000 4%);
}

.piano-keys .black.active, .piano-keys .black:active{
  box-shadow: inset -5px 5px 10px rgba(255, 255, 255,0.1);
  background: linear-gradient(to bottom, #000 0%, #434343);;
}

.piano-keys span {
  position: absolute;
  bottom: 20px;
  width: 100%;
  text-align: center;
  font-size: 1.13rem;
}

.piano-keys .key.hide span{
  display: none;
}

@media screen and (max-width: 815px) {
  header{
    flex-direction: column;
  }
  header :where(h2, .column) {
    margin-bottom: 13px;
  }
  .volume-slider input{
    width: 100px;
  }
  .piano-keys .key:where(:nth-child(9), :nth-child(10)) {
    display: none;
  }
  .piano-keys .black {
    height: 100px;
    width: 40px;
    margin: 0 -20px;
  }
  .piano-keys .white {
    height: 180px;
    width: 60px;
  }
}

@media screen and (max-width: 615px) {
  .piano-keys .key:nth-child(13),
  .piano-keys .key:nth-child(14),
  .piano-keys .key:nth-child(15),
  .piano-keys .key:nth-child(16),
  .piano-keys .key:nth-child(17){
    display: none;
  }
  .piano-keys .white{
    width: 50px;
  }
}