Result

jQuery

$(function() {
    //ウィンドウサイズの高さを取得して全体の高さを加える
    $("body").height($(window).height() + 2000);　$(window).scroll(function() {
        //一番上に行ったら最下部に、一番下に行ったら最上部にエフェクトなしで戻す
        if ($(window).scrollTop() >= ($("body").height() - $(window).height())) {$(window).scrollTop(1);
        }
        else if ($(window).scrollTop() == 0) {$(window).scrollTop($("body").height() - $(window).height() - 1);
        }
    });
});

css

body {
height: 2000px;
background: url("bg01.gif") ;
}
 

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