<div class="parent">
    <div class="label style">サンプルです</div>
    <img src="https://source.unsplash.com/600x400/?nature,water">
  </div>

  </div>

body {
	max-width: 600px;
	margin: 1em auto;
	display: flex;
	flex-wrap: wrap;
}

.parent {
	position: relative;
}
img {
	width: 100%;
	height: 100%;
	object-fit: cover;
}

.label {
	position: absolute;
	left: 50%;
	top: 50%;
	transform: translate(-50%, -50%);
	padding: 8px 25px;
	border-radius: 35px;
	font-size:2.5rem;
	font-weight: bold;
}

.label.style {
	background: #fff;
	color: #000;
	mix-blend-mode: screen;
}