style.css

html{
    position: relative;
    background-color: rgba(49, 25, 25, 0.884);
}
html:before{
    content: ' ';
    display: block;
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    opacity: 0.3;
    background-image: url('back.jpg');
    background-repeat: no-repeat;
    background-position: 50% 0;
    background-size: cover;
}

.keys {
    position: relative;
    width: 100%;
    height: 100%;
    display:flex;
    flex-direction: row;
    justify-content: center;
    align-items:center;
}
.key{
    background-color: rgba(49, 25, 25, 0.397);
    border: 3px solid white;
    border-radius: 5px;
    margin:30px;
    width: 90px;
    height: 90px;
    display:flex;
    flex-direction: column;
    justify-content: center;
    align-items:center;
    box-shadow:0 0 10px white;
    transition: all 0.5s; 
    /* ^make the transform smoothier and going backward */
}
kbd{
    color:white;
    font-size: 50px;
    transition: all 0.5s;
}
.playing kbd{ 
    text-shadow:0 0 10px rgb(255, 123, 0);
    transform:scale(1.1);
}
drumName{
    color: rgba(255, 166, 0, 0.795);
    font-size: 15px;
    transition: all 0.5s; 
}
.playing drumName{ 
    text-shadow:0 0 10px rgb(255, 123, 0);
    transform:scale(1.1);
}
.playing{
    transform: scale(1.1);
    border-color: rgb(255, 187, 0);
    box-shadow:0 0 10px rgb(255, 123, 0);
}