<svg xmlns="http://www.w3.org/2000/svg">
<defs>
    <clipPath id="clip">
        <rect x="20" y="20" width="160" height="160" rx="20" ry="20"/>
    </clipPath>
</defs>
<rect width="200" height="200" fill="green" clip-path="url(#clip)"/>
</svg>