.pastsenryu a {
  clear: both;
  display: block;
  width: 465px;
  height: 45px;
  background-repeat: no-repeat;
  margin: 10px 0 20px 100px;
  text-indent: -9999px;
  outline: none;
}
.pastsenryu a:hover {
  background-position: 0 -45px;
}
.senryu10 a {
  background-image: url(/convey/senryu/images/but_result10.gif);
}
.senryu11 a {
  background-image: url(/convey/senryu/images/but_result11.gif);
}
.senryu12 a {
  background-image: url(/convey/senryu/images/but_result12.gif);
}
.senryu13 a {
  background-image: url(/convey/senryu/images/but_result13.gif);
}
.senryu14 a {
  background-image: url(/convey/senryu/images/but_result14.gif);
}
.senryu15 a {
  background-image: url(/convey/senryu/images/but_result15.gif);
}