*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Quicksand', sans-serif;
}
body {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(to right bottom, #eeebf5, #f2cfee);
  }
  h2{
    color: #fff;
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 20px;
    font-weight: 600;
  }
  .wrapper {
    padding: 35px 40px;
    border-radius: 20px;
    background: #000000;
  }
  .wrapper header {
    display: flex;
    color: #cfcbcb;
    font-weight: 600;
    align-items: center;
    justify-content: space-between;
  }
  header .column {
    display: flex;
    align-items: center;
  }
  header span {
    font-weight: 500;
    margin-right: 15px;
    font-size: 1.19rem;
  }
  header input {
    outline: none;
    border-radius: 30px;
  }
  .volume-slider input {
    accent-color: #fff;
  }
  .volume-slider span, .keys-checkbox span {
    font-size: 1.5rem;
    font-weight: 600;
  }
  .keys-checkbox input {
    height: 30px;
    width: 60px;
    cursor: pointer;
    appearance: none;
    position: relative;
    background: #4B4B4B
  }
  .keys-checkbox input::before {
    content: "";
    position: absolute;
    top: 50%;
    left: 5px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #8c8c8c;
    transform: translateY(-50%);
    transition: all 0.3s ease;
  }
  .keys-checkbox input:checked::before {
    left: 35px;
    background: #fff;
  }
  .piano-keys {
    display: flex;
    margin-top: 40px;
  }
  .piano-keys .key {
    cursor: pointer;
    user-select: none;
    list-style: none;
    color: #a2a2a2;
    position: relative;
    text-transform: uppercase;
  }
  .piano-keys .black{
    width: 44px;
    height: 140px;
    z-index: 2;
    margin: 0 -22px 0 -22px;
    border-radius: 0 0 5px 5px;
    background: #000;
  }
  .piano-keys .black.active{
    box-shadow:inset -5px 5px 10px rgba(255,255,255,0.15);
    background: #191919;
  }
  .piano-keys .white{
    width: 70px;
    height: 230px;
    border-radius: 8px;
    border: 2.5px solid #000;
    background: #fff
  }
  .piano-keys .white.active{
    box-shadow:inset -5px 5px 20px rgba(0,0,0,0.2);
    background: #efefef;
  }
  .piano-keys span{
    position: absolute;
    bottom: 20px;
    width: 100%;
    font-size: 1.13rem;
    font-weight: 650;
    text-align: center;
  }
  .piano-keys .key.hide span{
    display: none;
  }

  @media (max-width:400px){
    h2{
        font-size: 1.5rem;
        margin-bottom: 10px;
      }
    .wrapper{
        margin-top: -330px;
        width: 90%;
        padding: 15px;
    }
    .header :where(.column){
        margin-bottom: 13px;
    }
    .volume-slider input{
        max-width: 80px;
        margin-left: -10px;
    }
    .volume-slider span, .keys-checkbox span {
        font-size: 0.9rem;
        font-weight: 400;
        margin-left: 15px;
        margin-right: 15px;
    }
    .keys-checkbox input {
        height: 26px;
        width: 60px;
        margin-left: -12px;
      }
    .piano-keys{
        margin-top: 20px;
        margin-left: 5px;
    }
    .piano-keys .black{
        height: 90px;
        width: 30px;
        margin: 0 -20px 0 -20px;
        
    }
    .piano-keys .white{
        height: 140px;
        width: 50px;
        border-radius: 10px;
        border-top: #f8f5f5;
        }  
    .piano-keys span{
        bottom: 15px;
        width: 100%;
        font-size: 0.9rem;
        text-align: center;
        text-decoration: none;
        padding-right: 1dvi;
        } 
  }