Nikolay_1984,
<!DOCTYPE html>
<html>
<head>
<title>Untitled</title>
<meta charset="utf-8">
<style type="text/css">
p{
height: 1500px;
}
</style>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>
$(function() {
$('a[href^="#"]').on("click", function(event) {
var target = $(this.getAttribute("href"));
var offsetDownLarge = 84;
var offsetDownSmall = 13;
if (target.length) {
event.preventDefault();
var clientWidth = document.body.clientWidth;
var offset = clientWidth >= 992 ? offsetDownLarge : offsetDownSmall;
var scroll = target.offset().top - offset;
$("html, body").stop().animate({scrollTop: scroll}, 700);
}
});
});
</script>
</head>
<body>
<a href="#slider" title="slider">slider</a>
<p></p>
<div id="slider">slider</div>
<p></p>
<script>
</script>
</body>
</html>