window.onload = function () {
 
    if (document.getElementById('InnerNav')){
 
    setMenuOffset.initialPos = getStyle('InnerNav','top');

    window.onscroll = document.documentElement.onscroll = setMenuOffset;
    setMenuOffset();
    
    }

}

function resizeDivTo(div_id){
 
  var div = document.getElementById(div_id);
    
  return div.offsetHeight;
}



function setMenuOffset() { 

  var header = document.getElementById('InnerNav');
  if (!header) return;
  var currentOffset = document.documentElement.scrollTop || document.body.scrollTop; // body for Safari
   
  var headHeight = resizeDivTo("Header") + resizeDivTo("PageHeader");
   
  var startPos = resizeDivTo("RelatedContent") + headHeight;
  var desiredOffset = startPos - currentOffset;
  if (desiredOffset < 10)
    desiredOffset = 10;

  //if (desiredOffset != parseInt(header.style.top)) 
    header.style.top = desiredOffset + 'px';
  
    //alert(resizeDivTo("RelatedContent"));
  
}


function getStyle(el,styleProp) {
  var x = document.getElementById(el);
  if (x.currentStyle)
    var y = x.currentStyle[styleProp];
  else if (window.getComputedStyle)
    var y = document.defaultView.getComputedStyle(x,null).getPropertyValue(styleProp);
  return y;
}