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

.cp_h1title {
  position: relative;
  color: #ffffff;
  background: #4db6ac;/*全体の背景（一番薄い色）*/
  overflow: hidden;/*はみ出た分を非表示に*/
  padding: 5px 10px;
}
.cp_h1title span {
  position: relative;
  z-index: 1;
}
.cp_h1title::before,
.cp_h1title::after {
  position: absolute;
  content: '';
  top: 0;
  left: 0;
  width: 110%;
  height: 100%;
}
.cp_h1title::before {
  background: #009688;/*2番目に薄い色*/
  transform-origin: bottom right;/*右下を起点に*/
  transform: rotate(1.5deg);/*1.5度傾斜*/
}
.cp_h1title::after {
  background: #00796b;/*3番目に薄い色*/
  transform-origin: bottom left;/*左下を起点に*/
  transform: rotate(-2.5deg);/*-2.5度傾斜*/
}