<h1 class="cp_h1title">見出しテキスト</h1>

.cp_h1title {
  position: relative;
  border-bottom: 1px solid #FFB300;
  padding: 0 0 0 35px;
}
.cp_h1title:before,
.cp_h1title:after {
  position: absolute;
  content: '';
  width: 17px;
  height: 17px;
  top: 30%;
  transform: rotate(45deg);
}
.cp_h1title:before {/*左のひし形*/
  border: 2px solid #FFB300;
  left: 3px;
}
.cp_h1title:after {/*右のひし形*/
  left: 10px;
  background: rgb(255, 179, 2, 0.5);
}