var maxop = 0.8; // 最大不透明度

var elsets = new Array();

for ( var i = 0 ; i < document.getElementsByClassName('pp_wrap').length ; i++ ) {
    elsets[i] = new Object();
    elsets[i].wrap = document.getElementsByClassName('pp_wrap')[i];
    elsets[i].trg = document.getElementsByClassName('pp_trg',elsets[i].wrap)[0];
    elsets[i].box = document.getElementsByClassName('pp_box',elsets[i].wrap)[0];
    elsets[i].box.id = 'pp_box_id_' + i;
}

for ( var i = 0 ; i < elsets.length ; i++ ) {
    elsets[i].box.style.visibility = 'visible';
    Element.setOpacity(elsets[i].box,0);
    elsets[i].trg.onmouseover = new Function ('','new Effect.Opacity($("' + elsets[i].box.id + '"),{from:0.0,to:maxop});');

    elsets[i].trg.onmouseout = new Function ('','new Effect.Opacity($("' + elsets[i].box.id + '"),{from:maxop,to:0.0});');
}