style.css

@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;700&display=swap');
*{
    padding: 0;
    margin: 0;
    box-sizing: border-box;
    font-family: 'Roboto', sans-serif;
}
body{
    background-image: url(backg.jpg);
    background-size: cover;
    background-attachment: fixed;
    background-repeat: no-repeat;
}
h2{
    display: flex;
    margin-top: 50px;
    justify-content: center;
    color: white;
    line-height: 40px;
    text-align: center;
}
.message{
    display: flex;
    flex-direction: column;
}
.keyboard{
    display: flex;
    justify-content: center;
    margin-top: 10px;
}
.keys{
    display: flex;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%,-50%);
}
.key{
    width: 100px;
    text-align: center;
    background-color: rgba(255, 255, 255, 0.432);
    margin: 0 30px;
    color: black;
    border: 2px solid white;
    border-radius: 2px;
    padding: 20px;
    font-size: 2rem;
    font-weight: 700;
    transition: all 0.07s;
}
.sound{
    text-align: center;
    color:yellow;
    font-size: 0.8rem;
    display: block;
    font-weight: 400;
}
.playing{
    transform: scale(1.1);
    border-color: blueviolet;
    box-shadow: 0 0 10px blueviolet;
}
.sound-i{
    position: absolute;
    border-radius: 50%;
    width: 80px;
    bottom: 10%;
    left: 1%;

}
@media screen and (max-width:600px) {
    .key{
        width: 70px;
        margin: 0 10px;
        font-size: 1.5rem;
        text-align: center;
    }
    .sound{
        font-size: 0.5rem;
        text-align: center;
    }
    .sound-i{
        width: 50px;
        bottom: 5%;
    }
    h2{
        font-size: 1rem;
        line-break: 600px;  
    } 
}