.login-box {
    width: 700px;
}
.login-box div.text-center input {
    width: 550px;
    height: 38px;
    display: inline-block;
}
.login-box div.text-center button {
    margin-top: -4px;
}

@media (max-width:768px) {
    .login-box {
        width: 100%;
    }
    .login-box div.text-center input {
        width: 200px;
        height: 38px;
    }
}

div.top-message {
    line-height: 3rem;
}

@media (max-width:768px) {
    div.top-message {
        font-size: 1.2rem;
        line-height: 2rem;
    }
}