// pagetop
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()", 25);
  }
}

// layervisibilty
nn4 = nn = ie = false; 
				if(document.all){//ie
					ie=true;
				}else if(document.layers){//nn4
					nn4=true;
				}else if(document.getElementById){//6up
					nn=true;
				}

				function setObj(n){
				var o;
				if(nn4){
					o = document.layers[n];
				}else if(ie){
					o = document.all[n];
				}else{
					o = document.getElementById(n);
				}
				return o;
				}

				function layerOn(n){
					var obj = setObj(n);
				if(nn4){
					obj.visibility = "show";
				}else{
					obj.style.visibility = "visible";
				}
					activeLayer = obj;
				}

				function layerOff(){
				if(activeLayer != null){
				if(nn4){
					activeLayer.visibility = "hide";
				}else{
					activeLayer.style.visibility ="hidden";
				}
					activeLayer = null
				}
				}

				activeLayer = null


//��������܂�				
function PrintPage(){
	if(document.getElementById || document.layers){
		window.print();	
	}
}