css sticky top code example

Example 1: sticky operations in javascript

var siteHeader = document.getElementById('siteHeader'),
    siteNav = document.getElementById('siteNav');

    window.onscroll = function() {
        if ( siteNav.offsetTop < document.documentElement.scrollTop + 26 || siteNav.offsetTop < document.body.scrollTop + 26) {
            siteHeader.setAttribute("class","sticky");
        }
        else {
            siteHeader.setAttribute("class","");
        }
    }

Example 2: make a div sticky

.fixedElement {
    background-color: #c0c0c0;
    position:fixed;
    top:0;
    width:100%;
    z-index:100;
}