/*マーカーアニメーション*/
.under_marker.active{
  background-position: -100% .5em;
}

.under_marker {
  background-image: -webkit-linear-gradient(left, transparent 50%, rgb(253,215,201) 50%);
  background-image: -moz-linear-gradient(left, transparent 50%, rgb(253,215,201) 50%);
  background-image: -ms-linear-gradient(left, transparent 50%, rgb(253,215,201) 50%);
  background-image: -o-linear-gradient(left, transparent 50%, rgb(253,215,201) 50%);
  background-image: linear-gradient(left, transparent 50%, rgb(253,215,201) 50%);
  background-repeat: repeat-x;
  background-size: 200% .8em;
  background-position: 0 .5em;
  transition: all 1s ease;
  font-weight: bold;
}