<!DOCTYPE html>
<html lang="">
<head>
<title>Chess Pattern</title>
<style>
.chessboard-container {
position: fixed;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
width: 400px;
height: 400px;
border: 5px solid #333;
overflow: hidden;
}
.chessboard {
width: 100%;
height: 100%;
background-size: 50px 50px;
background-image:
linear-gradient(45deg, #000 25%, transparent 25%,
transparent 75%, #000 75%, #000),
linear-gradient(45deg, #000 25%, transparent 25%,
transparent 75%, #000 75%, #000),
linear-gradient(45deg, #fff 25%, transparent 25%,
transparent 75%, #fff 75%, #fff),
linear-gradient(45deg, #fff 25%, transparent 25%,
transparent 75%, #fff 75%, #fff);
background-position: 0 0, 25px 25px, 25px 0, 0 25px;
}
</style>
</head>
<body>
<div class="chessboard-container">
<div class="chessboard"></div>
</div>
</body>
</html>