function SmoothScroll(targetID){
  if( !document.getElementById ) {return true;}
  var step=20;  //初速度
  var max=400;  //最高速度
  var accel=10;  //加速度
  var interval=40;  //加速インターバル
  var current_y = document.body.scrollTop  || document.documentElement.scrollTop;
  var element=document.getElementById(targetID);
  if (!element){return true;}
  var target_y = 0;
  for (i = element;i.offsetParent;i=i.offsetParent ){
    target_y += i.offsetTop;
  }
  var count=0;
  if ( current_y > target_y ){ step = -(step); accel = -(accel);}
  var timerid = setInterval( function(){
    if (step<max) step += (count*accel);
    if ( Math.abs(current_y-target_y) < Math.abs(step) ){
      window.scrollTo((document.body.scrollTop  || document.documentElement.scrollTop),target_y);
      clearInterval(timerid);
      return false;
    }else{
      window.scrollBy(0,step);
      current_y += step;
      count++;
    }
  },interval);
  return false;
}

/*
<a href="ここにID" onclick="return SmoothScroll( 'ここにID' );">じゃんぷ</a>
*/



/*


function backToTop() {
  var x1 = x2 = x3 = 0;
  var y1 = y2 = y3 = 0;
  if (document.documentElement) {
      x1 = document.documentElement.scrollLeft || 0;
      y1 = document.documentElement.scrollTop || 0;
  }
  if (document.body) {
      x2 = document.body.scrollLeft || 0;
      y2 = document.body.scrollTop || 0;
  }
  x3 = window.scrollX || 0;
  y3 = window.scrollY || 0;
  var x = Math.max(x1, Math.max(x2, x3));
  var y = Math.max(y1, Math.max(y2, y3));
  window.scrollTo(Math.floor(x / 2), Math.floor(y / 2));
  if (x > 0 || y > 0) {
      window.setTimeout("backToTop()", 40);
  }
}
*/

/*

<a href="#top" onclick="backToTop(); return false" onkeypress="backToTop(); return false">ɖ߂B</a>

*/


/* Window Open
--------------------------------------------*/
// New window open
function OpenWin(){
    win=window.open("popup.html","new","width=640,height=600,scrollbars=yes");
}

