<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1400 1400">
  <defs>
    <linearGradient id="gradient" x1="661.5" y1="364.6" x2="830.04" y2="2244.44" gradientTransform="matrix(1 0 0 1 0 36)" gradientUnits="userSpaceOnUse">
      <stop offset="0" stop-color="#1B1319" stop-opacity="0"/>
      <stop offset="1" stop-color="#1B1319"/>
    </linearGradient>
  </defs>
  <rect y="260" width="1400" height="1140" fill="url(#gradient)"/>
  <polygon points="0,1400 1400,1153.1 1400,1400" fill="#FFFFFF"/>
</svg>
