section {
	display: grid;
	grid-template-columns: repeat(4, 1fr);
	grid-auto-flow: dense;
}

div:nth-child(3),
div:nth-child(6) {
	grid-column: span 2;
	grid-row: span 2;
}
body {
	font-family: sans-serif;
	padding: 20px;
}

section {
	background-color: gold;
}

div {
	background-color: tomato;
	border-bottom: 2px solid firebrick;
	border-right: 2px solid firebrick;
	padding: 5px;
}
<!DOCTYPE html>
<html>
	<head>
		<meta name="viewport" content="width=device-width, initial-scale=1">
		<link href="/assets/styles/reset.css" rel="stylesheet">
		<link href="setup.css" rel="stylesheet">
		<link href="style.css" rel="stylesheet">
	</head>
	<body>
		<section>
			<div>
				<p>Item 1</p>
			</div>
			<div>
				<p>Item 2 <br>with line <br>breaks</p>
			</div>
			<div>
				<p>Item 3 <br>also</p>
			</div>
			<div>
				<p>Item 4</p>
			</div>
			<div>
				<p>Item 5</p>
			</div>
			<div>
				<p>Item 6</p>
			</div>
			<div>
				<p>Item 7 with more text</p>
			</div>
			<div>
				<p>Item 8</p>
			</div>
			<div>
				<p>Item 9 longer</p>
			</div>
			<div>
				<p>Item 10</p>
			</div>
			<div>
				<p>Item 11</p>
			</div>
		</section>
	</body>
</html>