背景色と線

HTML

<a href="">私たちについて</a>

CSS

a {
  display: block;
  position: relative;
  padding: 30px;
  width: 260px;
  color: #333;
  font-size: 18px;
  font-weight: 700;
  text-decoration: none;
  background-color: #90be70;
  border-radius: 20px;
}

a::after {
  content: '';
  position: absolute;
  top: 50%;
  right: 0;
  transform: translateY(-50%);
  width: 50px;
  height: 2px;
  background-color: #2b550e;
}