var arg = 'scroll';
var stop = false;
var top_margin = 0
var offset = 0;

function scrollup(arg) {
  offset = document.getElementById(arg).clientHeight-1182;
  if (top_margin<offset && stop==false)
  {
    top_margin = top_margin+20;
    document.getElementById(arg).style.marginTop='-'+top_margin+'px';
    setTimeout("scrollup(arg)", 10);
  }
  else
  {
    stop = false;
    return;
  }
}

function scrolldown(arg) {
  if (top_margin>0 && stop==false)
  {
    top_margin = top_margin-20;
    document.getElementById(arg).style.marginTop='-'+top_margin+'px';
    setTimeout("scrolldown(arg)", 10);
  }
  else
  {
    stop = false;
    return;
  }
}

function scrollstop() {
   stop = true;
}

function scrollstart() {
   stop = false;
}