<h1 class="cp_h1title">見出しテキスト</h1>

.cp_h1title {
	position: relative;
	padding: .3em .3em .3em 2.3em;
	background: #FFCA28;
	color: #fff;
}
.cp_h1title:before {
	position: absolute;
	content: '';
	left: 0px;
	top: 0px;
	border: none;
	border-left: solid 2em #fafcfc;
	border-bottom: solid 2em transparent;
}