body {
    background-image: url(img/Background.jpg);
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-size: cover;
}

.center {
    display: block;
    margin-left: auto;
    margin-right: auto;
}

.navbar-nav>li {
    padding-left: 20px;
    padding-right: 20px;
}