body{
    text-align: center;
}
.btn{
    height: 100px;
    width: 100px;
    border-radius: 20%;
    border: 5px solid black;
    margin: 2rem;
}
.btn-container{
    display: flex;
justify-content: center;
}
.red{
    background-color: red;
}
.yellow{
    background-color: yellow;
}
.green{
    background-color: green;
}
.purple{
    background-color: purple;
}
.flash{
    background-color: white;

}

.userflash{
    background-color: aqua;
}