/***************************************
* top button 
***************************************/ 
ScroolTop = function(className, id) {
  this.IE = document.all ? 1 : 0;
  this.NN = document.layer ? 1 : 0;
  this.N6 = document.getElementById ? 1 : 0;
  if(this.IE) this.layer = document.all(id);
  else if(this.NN) this.layer = document.layer[id];
  else if(this.N6) this.layer = document.getElementById(id);
  else return;
  this.className = className;
  this.top = this.oldY = parseInt(this.layer.style.top,10);
  setInterval(this.className + ".move()", 10);
}
ScroolTop.prototype.move = function() {
    var diffY = (this.IE) ? document.body.scrollTop+this.top : self.pageYOffset+this.top; // Ç¥ÁØ¿¡´Â document.documentElement.scrollTop
    if(diffY != this.oldY) {
        var percentY = .1 * (diffY - this.oldY);
        percentY = (percentY > 0) ? Math.ceil(percentY) : Math.floor(percentY);

        this.oldY += percentY;
        this.layer.style.top = this.oldY + "px";
    }
}

function goTop(orix,oriy,desx,desy) {
  var Timer;
  var winHeight = document.body.scrollTop;
  if(Timer) clearTimeout(Timer);
  startx = 0;
  starty = winHeight;
  if(!orix || orix < 0) orix = 0;
  if(!oriy || oriy < 0) oriy = 0;
  var speed = 7;
  if(!desx) desx = 0 + startx;
  if(!desy) desy = 0 + starty;
  desx += (orix - startx) / speed;
  if (desx < 0) desx = 0;
  desy += (oriy - starty) / speed;
  if (desy < 0) desy = 0;
  var posX = Math.ceil(desx);
  var posY = Math.ceil(desy);
  window.scrollTo(posX, posY);
  if((Math.floor(Math.abs(startx - orix)) < 1) && (Math.floor(Math.abs(starty - oriy)) < 1)){
    clearTimeout(Timer);
    window.scroll(orix,oriy);
  }else if(posX != orix || posY != oriy){
    Timer = setTimeout("goTop("+orix+","+oriy+","+desx+","+desy+")",15);
  }else{
    clearTimeout(Timer);
  }
}