#roll_top, #fall, #ct {
  position: relative;
  cursor: pointer;
  height: 41px;
  width: 36px;
  z-index: 10;
}

#roll_top {
  background: url(../images/common/top.gif) no-repeat;
}

#fall {
  background: url(../images/common/top.gif) no-repeat 0 -80px;
}

#ct {
  background: url(../images/common/top.gif) no-repeat 0 -40px;
}

#roll {
  display: block;
  width: 15px;
  margin-right: -500px;
  position: fixed;
  right: 50%;
  top: 66%;
  _margin-right: -505px;
  _position: absolute;
  _margin-top: 300px;
  _top: expression(eval(document.documentElement.scrollTop));
}