body{
    display:flex;
    justify-content: center;
    align-items: center;
    height:100vh;
    background: #343a40;
    color:white;
    margin:0;
}
.box{
    display:flex;
    flex-direction: column;
    justify-content: center;
    align-content: center;
    background-color: #495057;
    padding:2rem;
}