<ul class="example">
	<li>STEP.01</li>
	<li>STEP.02</li>
	<li>STEP.03</li>
	<li>STEP.04</li>
</ul>

* {
	box-sizing: border-box;
}
body {
	min-height: 100vh;
	background: #dce4ec;
	margin: 0;
	padding: 20px;
	display: flex;
	justify-content: center;
	align-items: center;
}
ul {
	padding: 0;
}

.example {
	width: 100%;
	display: table;
	table-layout: fixed;
}
.example > li {
	display: table-cell;
	font-size: 18px;
	font-weight: bold;
	color: #5f7c97;
	background: #bacee1;
	padding: 20px;
	text-align: center;
	position: relative;
}
.example > li:not(:last-of-type)::after {
	content: "";
	display: block;
	border-style: solid;
	border-width: 15px 0 15px 10px;
	border-color: transparent transparent transparent #5f7c97;
	position: absolute;
	top: -webkit-calc(50% - 15px);
	top: calc(50% - 15px);
	left: 100%;
	z-index: 10;
}