sticky headline

function initHeadline_sticky()
      {
        console.log('[DFP] initiate Headline stickiness');
            var dfpOnceSticky = false, hlStart = 0, hlStickyTimer;
        document.addEventListener("scroll", function(){
            var dfpHL = document.getElementById("div-gpt-ad-liputan6-hl");
            var hlPos = dfpHL.getBoundingClientRect();
            if(!dfpOnceSticky && hlPos.top<=10){
                hlStart = dfpHL.offsetTop;
                dfpHL.classList.add("dfp-hl-sticky");
                dfpOnceSticky = true;
                dfp_videoHLStickyState = dfpOnceSticky;
                hlStickyTimer = window.setTimeout(function() {
                    dfpHL.style.marginTop = -(dfpHL.clientHeight)+"px"
                    setTimeout(function() {
                        dfpHL.classList.remove("dfp-hl-sticky");
                        dfpHL.style.marginTop = "0px";
                    }, 700);
                }, 5000);
            }
            if(dfpOnceSticky && window.scrollY < (hlStart-70) && hlStickyTimer){
                window.clearTimeout(hlStickyTimer);
                dfpHL.classList.remove("dfp-hl-sticky");
                dfpHL.style.marginTop = "10px";
            }
        });
      }