<div class="simpleButton">
  <a href="#">詳細はこちら</a>
</div>
                

.simpleButton a {
  color: #000;
  display: inline-block;
  position: relative;
  padding: 0.8em 2.8em 0.8em 1.5em;
  position: relative;
}
.simpleButton a::after {
  content: "";
  width: 0.4em;
  height: 0.8em;
  display: block;
  background: url("/img/icon/caret-right.svg") no-repeat center center;
  background-size: 100% auto;
  position: absolute;
  top: 50%;
  right: 1em;
  margin-top:-0.4em;
  transition: all 0.5s;
}
.simpleButton a::before {
  content: '';
  width: 100%;
  height: 0.2em;
  display:block;
  background: rgba(0,0,0,.6);
  position: absolute;
  top:100%;
  left: 0;
  border-radius: 0.1em;
  transition: .4s;
}
.simpleButton a:hover {
  color: #000;
}
.simpleButton a:hover::after {
  right: 0.8em;
}
.simpleButton a:hover::before {
  top: calc(100% - 0.2em);
}
              

.simpleButton a {
  color: #000;
  display: inline-block;
  position: relative;
  padding: 0.8em 2.8em 0.8em 1.5em;
  position: relative;
  &::after {
    content: "";
    width: 0.4em;
    height: 0.8em;
    display: block;
    background: url("/img/icon/caret-right.svg") no-repeat center center;
    background-size: 100% auto;
    position: absolute;
    top: 50%;
    right: 1em;
    margin-top:-0.4em;
    transition: all 0.5s;
  }
  &::before {
    content: '';
    width: 100%;
    height: 0.2em;
    display:block;
    background: rgba(0,0,0,.6);
    position: absolute;
    top:100%;
    left: 0;
    border-radius: 0.1em;
    transition: .4s;
  }
  &:hover {
    color: #000;
    &::after {
      right: 0.8em;
    }
    &::before {
      top: calc(100% - 0.2em);
    }
  }
}