@media (min-width:1200px) {
    html {
        background-image: url('../images/bg.gif');
    }
    body, html, .container, .body-container, .main-content .navbar-fixed .navbar-inner {
        width: 100% !important;
        /*width: 1290px !important;*/
        width: calc(100vw - 15rem) !important;
        margin-right: auto;
        margin-left: auto;
    }
}