style.css

.piano {
    display: flex;
    top: 50%;
    position: absolute;
    transform: translateY(-50%);
    height: 200px;
    text-align: center;
}

.piano * {
    width: 50px;
    height: 100%;
    background-color: rgb(255, 255, 255);
    margin: 1px;
    border: 1px solid black;
    border-radius: 10px;
}

.piano h1 {
    width: 0;
    height: 0;
    background-color: transparent;
    margin: 0;
    border: 0px solid black;
    position: relative;
    top: 70%;
    pointer-events: none;
}

.csh,
.dsh,
.fsh,
.gsh,
.ash {
    height: 60%;
    background-color: black;
    color: white;
    width: 40px;
}

.piano *:hover {
    background-color: rgb(140, 101, 230);
    box-shadow: 0 0 5px 5px rgb(1, 255, 77);
}

.csh {
    position: absolute;
    left: 7.5%;
}

.dsh {
    position: absolute;
    left: 22.5%;
}

.fsh {
    position: absolute;
    left: 50.5%;
}

.gsh {
    position: absolute;
    left: 66%;
}

.ash {
    position: absolute;
    left: 80%;
}