scroll down navigation bar fixed

Css Code :-

.fixed{  /* To fix main menu container */
z-index: 9999;
position: fixed;
left: 0;
top: 0;
width: 100%;
left:0px;
background-color: #fff;
box-shadow: 7px 1px 6px #d4d4d4;
animation-name: up;
animation-duration: 0.5s;
animation-iteration-count: 1;
}

.fixed .anima{
animation-name: up;
animation-duration: 0.5s;
animation-iteration-count: 1;
border-bottom: 1px solid #c7c5c5;
padding-bottom: 5px;

}


@keyframes up{

0%{
transform: translateY(-100%);
}
100%{
transform: translateY(0%);
}

}




Js Code:-

<script type="text/javascript">
$(window).bind('scroll', function () {
    if ($(window).scrollTop() > 200) {
        $('.navbar-default').addClass('fixed');
    } else {
        $('.navbar-default').removeClass('fixed');
    }
});


</script>