// レイアの最初の横位置
def_left = 20;
// レイアの最初の縦位置
def_top = 30;
function init() {
   N4 = IE = GK = 0;
   if (document.layers)
      { N4 ++; obj = document.layers["lay"]; }
   else if (document.all)
      { IE ++; obj = document.all("lay").style; }
   else if (document.getElementById)
      { GK ++; obj = document.getElementById("lay").style; }

   with (obj) {
      left = def_left;
      top = def_top;
   }
   lay_ud();
}

function lay_ud() {
   if (N4) y = pageYOffset + def_top;
   if (IE) y = document.body.scrollTop + def_top;
   if (GK) y = window.pageYOffset + def_top;
   obj.top = y;
   setTimeout("lay_ud()",0);
}

onload = init;