body{
    text-align: center;
}
.btn{
    height: 100px;
    width: 100px;
    border-radius: 50%;
    margin: 0.5rem;
    border: 5px solid black;
}
.btn-container{
    display:flex ;
    justify-content:center ;
}
.yellow{
    background-color: yellow;

}
.blue{
    background-color: blue;
}
.green{
    background-color: rgba(25, 242, 25, 0.94);
}
.red{
    background-color: red;
}
.flash{
    background-color:white ;
}
.userflash{
    background-color: hotpink;
}