Scroll_fixed_header.js

document.getElementById("header").style.top = 0;
var prevScrollpos = window.pageYOffset;
window.onscroll = function() {
    document.getElementById("header").style.position = 'fixed';
var currentScrollPos = window.pageYOffset;
var htop = parseInt(document.getElementById("header").style.top);
var menuHeight = $('header').outerHeight()+5;
  if (prevScrollpos > currentScrollPos) {
htop = htop +3;
console.log("Top"+ htop);
if(htop<=0)
    document.getElementById("header").style.top = htop+"px";
  } else {
htop = htop -3;
console.log("Bottom"+ htop);
if(htop<0 && htop>-menuHeight)
{
document.getElementById("header").style.top = htop+"px";
}
  }
  prevScrollpos = currentScrollPos;
}


//Standard Method

document.getElementById("header").style.top = 0;
var menuHeight = $('header').outerHeight()+5;
document.getElementById("block").style.paddingTop = menuHeight+"px";
var prevScrollpos = window.pageYOffset;
window.scrolldir = 1;
window.onscroll = function() {
    document.getElementById("header").style.position = 'fixed';
var currentScrollPos = window.pageYOffset;
var htop = parseInt(document.getElementById("header").style.top);
if(scrolldir<-25 || scrolldir>150)
scrolldir = 1;
 if (prevScrollpos > currentScrollPos) {
htop = htop +3;
scrolldir = scrolldir+3;
console.log("Top"+ htop);
if(scrolldir>145)
    document.getElementById("header").style.top = "0px";
  } else {
scrolldir = scrolldir-3;
htop = htop -3;
console.log("Bottom"+ htop);
if(scrolldir<-20)
{
document.getElementById("header").style.top = -window.menuHeight+"px";
}
  }
  prevScrollpos = currentScrollPos;
}