Untitled

body {
    padding-top: 65px;
}

#godown{
   height: 60px;
}

<body>
<nav class="navbar navbar-fixed-top " role="navigation" id="navMenu">
...

</nav>

<!-- This div make the magic :) -->

<div class="godown-60" id="godown"></div>

<!-- the rest of your site -->
...

<script>
//insert this in your jquery
//control the resizing of menu and go down the content in the correct position

    $("#navMenu").resize(function () {
        $('#godown').height($("#navMenu").height() + 10);
    });

    if ($("#navMenu").height() > $('#godown').height()) $('#godown').height($("#navMenu").height() + 10);

</script>

// add appropriate media query if required to target mobile nav only
.nav { overflow-y: hidden !important }