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

.simpleButton a {
  color: #000;
  border: #000 solid 2px;
  display: inline-block;
  line-height: 1.4em;
  padding: 0.5em 3em 0.5em 1.8em;
  background: transparent;
  border-radius: 1.4em;
  vertical-align: bottom;
  position: relative;
  overflow: hidden;
  transition: 0.3s all ease;
}
.simpleButton a::after {
  content: "";
  width: 0.8em;
  height: 0.8em;
  display: block;
  background: url("/img/icon/arrow-circle-right.svg") no-repeat center center;
  background-size: 100% auto;
  position: absolute;
  top: 50%;
  right: 1.4em;
  margin-top: -0.4em;
  transition: 0.3s all ease;
}
.simpleButton a:hover {
  color: #fff;
  background-color: #000;
}
.simpleButton a:hover::after {
  right: 1em;
  filter: brightness(0) saturate(100%) invert(100%) sepia(0%) saturate(0%)
    hue-rotate(228deg) brightness(106%) contrast(101%);
}
              

.simpleButton{
 a {
  color: #000;
  border: #000 solid 2px;
  display: inline-block;
  line-height: 1.4em;
  padding: 0.5em 3em 0.5em 1.8em;
  background: transparent;
  border-radius: 1.4em;
  vertical-align: bottom;
  position: relative;
  overflow: hidden;
  transition: 0.3s all ease;
 }
  &::after {
    content: "";
    width: 0.8em;
    height: 0.8em;
    display: block;
    background: url("/img/icon/arrow-circle-right.svg") no-repeat center center;
    background-size: 100% auto;
    position: absolute;
    top: 50%;
    right: 1.4em;
    margin-top: -0.4em;
    transition: 0.3s all ease;
  }
  &:hover {
    color: #fff;
    background-color: #000;
    &::after {
      right: 1em;
      filter: brightness(0) saturate(100%) invert(100%) sepia(0%) saturate(0%)
        hue-rotate(228deg) brightness(106%) contrast(101%);
    }
  }
}