var contentPos;
window.onload = function(){
    contentPos = Math.round((document.body.offsetWidth - 865) / 2);
    ScrollMenu();
};
window.onscroll = ScrollMenu;
function ScrollMenu(){
    if(getScrollXY() > 229) {
        document.getElementById("rightContent").style.position = "fixed";
        document.getElementById("rightContent").style.right = contentPos + "px";  
    }      
    else {
        document.getElementById("rightContent").style.position = "relative";
        document.getElementById("rightContent").style.right = "0px";
    }
        
}
function getScrollXY() {
  var scrOfX = 0, scrOfY = 0;
  if( typeof( window.pageYOffset ) == 'number' ) {
    //Netscape compliant
    scrOfY = window.pageYOffset;
    scrOfX = window.pageXOffset;
  } else if( document.body && ( document.body.scrollLeft || document.body.scrollTop ) ) {
    //DOM compliant
    scrOfY = document.body.scrollTop;
    scrOfX = document.body.scrollLeft;
  } else if( document.documentElement && ( document.documentElement.scrollLeft || document.documentElement.scrollTop ) ) {
    //IE6 standards compliant mode
    scrOfY = document.documentElement.scrollTop;
    scrOfX = document.documentElement.scrollLeft;
  }
  return scrOfY;
}