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()", 50);
  }
}



// パージ内リンク対応

$(function(){
	$('a[href^=#]').click(function(){
		var speed = 500;
		var href= $(this).attr("href");
		var target = $(href == "#" || href == "" ? 'html' : href);
		var position = target.offset().top;
		$("html, body").animate({scrollTop:position}, speed, "swing");
		return false;
	});
});