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<svg xmlns="http://www.w3.org/2000/svg" width="100%" height="100%" style="margin: 2rem auto">
    <style type="text/css">
        #checkerboard { fill: #ccc; }
    </style>
    <defs>
        <pattern id="checkerboard" patternUnits="userSpaceOnUse" width="50" height="50">
            <rect x="0" y="0" width="25" height="25"></rect>
            <rect x="25" y="25" width="25" height="25"></rect>
        </pattern>
    </defs>
    <rect width="100%" height="100%" fill="url(#checkerboard)"></rect>
</svg>