//         =======================��ļс��800px�����զ�����=========================
window.onresize = function () {
    var win = $(window).width(),
        main = $('#main');
        img = $('#df');
    if (win < 1349) {
        main.addclass('min-800');
        img.hide();
    }
    else {
        main.removeclass('min-800');
        img.show();
    }
};