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

.simpleButton a {
  color: #cccccc;
  background-color: #000;
  background-image: -webkit-linear-gradient(135deg, #000, #666666);
  background-image: linear-gradient(-45deg, #000, #666666);
  border-top: #666666 solid 1px;
  border-left: #4d4d4d solid 1px;
  border-right: #4d4d4d solid 1px;
  border-bottom: #000 solid 1px;
  display: inline-block;
  line-height: 1.4em;
  padding: 0.6em 3em 0.6em 1.6em;
  border-radius: 0.25em;
  vertical-align: bottom;
  box-shadow: 0 1.31em 0 0 rgba(255, 255, 255, 0.1) inset;
  transition: 0.3s all ease;
  position: relative;
}
.simpleButton a::after {
  content: "";
  width: 0.4em;
  height: 0.8em;
  display: block;
  background: url("/img/icon/angle-right.svg") no-repeat center center;
  background-size: 100% auto;
  filter: brightness(0) saturate(100%) invert(100%) sepia(0%) saturate(0%)
    hue-rotate(228deg) brightness(106%) contrast(101%);
  position: absolute;
  top: 50%;
  right: 1.4em;
  margin-top: -0.4em;
  transition: 0.3s all ease;
}
.simpleButton a:hover {
  color: #fff;
  background-image: linear-gradient(-45deg, #1a1a1a, #666666);
  box-shadow: 0 1.31em 0 0 rgba(255, 255, 255, 0.05) inset;
}
.simpleButton a:hover::after {
  right: 1.2em;
}
              

.simpleButton a {
  color: #cccccc;
  background-color: #000;
  background-image: -webkit-linear-gradient(135deg, #000, #666666);
  background-image: linear-gradient(-45deg, #000, #666666);
  border-top: #666666 solid 1px;
  border-left: #4d4d4d solid 1px;
  border-right: #4d4d4d solid 1px;
  border-bottom: #000 solid 1px;
  display: inline-block;
  line-height: 1.4em;
  padding: 0.6em 3em 0.6em 1.6em;
  border-radius: 0.25em;
  vertical-align: bottom;
  box-shadow: 0 1.31em 0 0 rgba(255, 255, 255, 0.1) inset;
  transition: 0.3s all ease;
  position: relative;
  &::after {
    content: "";
    width: 0.4em;
    height: 0.8em;
    display: block;
    background: url("/img/icon/angle-right.svg") no-repeat center center;
    background-size: 100% auto;
    filter: brightness(0) saturate(100%) invert(100%) sepia(0%) saturate(0%)
      hue-rotate(228deg) brightness(106%) contrast(101%);
    position: absolute;
    top: 50%;
    right: 1.4em;
    margin-top: -0.4em;
    transition: 0.3s all ease;
  }
  &:hover {
    color: #fff;
    background-image: linear-gradient(-45deg, #1a1a1a, #666666);
    box-shadow: 0 1.31em 0 0 rgba(255, 255, 255, 0.05) inset;
    &::after {
      right: 1.2em;
    }
  }
}