<style>

.markdown-body .anchor{
    float: left;
    margin-top: -8px;
    margin-left: -20px;
    padding-right: 4px;
    line-height: 1;
    opacity: 0;
}

.markdown-body .anchor .anchor-icon{
    font-size: 15px
}

</style> <script>

$(document).ready(function() {
    let nodes = document.querySelector(".markdown-body").querySelectorAll("h1,h2,h3")
    for(let node of nodes) {
        var anchor = document.createElement("a")
        var anchorIcon = document.createElement("i")
        anchorIcon.setAttribute("class", "fa fa-anchor fa-lg anchor-icon")
        anchorIcon.setAttribute("aria-hidden", true)
        anchor.setAttribute("class", "anchor")
        anchor.setAttribute("href", "#" + node.getAttribute("id"))

        anchor.onmouseover = function() {
            this.style.opacity = "0.4"
        }

        anchor.onmouseout = function() {
            this.style.opacity = "0"
        }

        anchor.appendChild(anchorIcon)
        node.appendChild(anchor)
    }
})

</script>