body {
    height: 100vh;
    width: auto;
    background-color:lightblue !important;
}

.login-box {
    width: 500px; 
    height: 400px; 
    margin: auto;
}


@media screen and (max-width: 500px) {
    .login-box {
        height: 400px; 
        width: 100%;
    }
}