function fadeAnime(){
  $('.fadeUpTrigger').not('.done').each(function(){
    var elemPos = $(this).offset().top - 50;
    var scroll = $(window).scrollTop();
    var windowHeight = $(window).height();
    if (scroll >= elemPos - windowHeight){
      $(this).addClass('fadeUp done');
    }
  });

  $('.fadeDownTrigger').not('.done').each(function(){
    var elemPos = $(this).offset().top - 50;
    var scroll = $(window).scrollTop();
    var windowHeight = $(window).height();
    if (scroll >= elemPos - windowHeight){
      $(this).addClass('fadeDown done');
    }
  });

  $('.fadeRightTrigger').not('.done').each(function(){
    var elemPos = $(this).offset().top - 50;
    var scroll = $(window).scrollTop();
    var windowHeight = $(window).height();
    if (scroll >= elemPos - windowHeight){
      $(this).addClass('fadeRight done');
    }
  });

  $('.fadeLeftTrigger').not('.done').each(function(){
    var elemPos = $(this).offset().top - 50;
    var scroll = $(window).scrollTop();
    var windowHeight = $(window).height();
    if (scroll >= elemPos - windowHeight){
      $(this).addClass('fadeLeft done');
    }
  });

  $('.zoomInTrigger').not('.done').each(function(){
    var elemPos = $(this).offset().top - 50;
    var scroll = $(window).scrollTop();
    var windowHeight = $(window).height();
    if (scroll >= elemPos - windowHeight){
      $(this).addClass('zoomIn done');
    }
  });
}

// 実行タイミング：読み込み時とスクロール時
$(window).on('load scroll', function(){
  fadeAnime();
});