<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 64 64" width="64" height="64">
  <defs>
    <linearGradient id="g" x1="0" y1="0" x2="1" y2="1">
      <stop offset="0" stop-color="#2f7bf6"/>
      <stop offset="1" stop-color="#7ad6ff"/>
    </linearGradient>
  </defs>
  <rect width="64" height="64" rx="14" fill="#070b12"/>
  <rect x="1.5" y="1.5" width="61" height="61" rx="12.5" fill="none" stroke="#1b2a3d"/>
  <text x="32" y="43" font-family="Archivo, Arial, sans-serif" font-size="30" font-weight="800" text-anchor="middle" fill="url(#g)">OK</text>
</svg>
