2色の線を重ねた見出し – 疑似要素

HTML

<h2 class="heading">採用情報について</h2>

CSS

.heading {
  position: relative;
  padding-bottom: 24px;
  width: 100%;
  font-size: 26px;
  border-bottom: 5px solid #c7c7c7;
}

.heading::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 0;
  width: 70px;
  height: 5px;
  background-color: #e5c046;
}