<svg xmlns="http://www.w3.org/2000/svg">
  <defs>
    <linearGradient id="grad">
      <stop offset="0%" stop-color="papayawhip" />
      <stop offset="100%" stop-color="plum" />
    </linearGradient>
  </defs>

  <rect x="50" y="50" width="100" height="100" fill="url(#grad)" />
</svg>