<h1 class="cp_h1title"><span>見出しテキスト</span></h1>

.cp_h1title {
  position: relative;
  color: #ffffff;
  background-color: #ffb300;
  border-radius: 3px;
  transform: skewX(-15deg);
  padding: 5px 10px;
}
.cp_h1title::after {/*カギ括弧*/
  position: absolute;
  content: '';
  width: 90px;
  height: 20px;
  border: solid #ffecb3;
  border-width: 0 1px 1px 0;
  border-radius: 0 0 3px 0;
}
.cp_h1title::after {
  right: 3px;
  bottom: 3px;
}