What is wrong in this SVG file? Why doesnt the forum accept it?

<svg viewBox="0 0 300 300" xmlns="http://www.w3.org/2000/svg" xmlns:svg="http://www.w3.org/2000/svg">
<defs id="defs">
<radialGradient id="gr">
<stop id="st1" offset="0" stop-color="#660000"/>
<stop id="st2" offset="0.5" stop-color="#c30000"/>
<stop id="st3" offset="1" stop-color="#a00000"/>
</radialGradient>
</defs>
<g class="layer">
<title>Layer 1</title>
<circle cx="150" cy="150" fill="url(#gr)" id="iris" r="145" stroke="#000" stroke-width="10"/>
<path d="m177.6,10.7c-42.6,57.7 -22.2,90 2.2,107.8c81.1,42.1 95,96 76.1,126.4c-18.6,-53 -57.9,-72.5 -97.4,-50c-71.6,43.7 -117.8,36.3 -142.8,1.7c42.5,6.5 93.4,-3.1 92.2,-68.3c1.6,-30.7 3.6,-111.7 69.7,-117.6z" fill="#000" id="tomoe"/>
<circle cx="150" cy="150" fill="#a00000" id="center" r="20"/>
</g>
<animateTransform attributeName="transform" type="rotate" repeatCount="indefinite" dur="1.5s" values="360;0" begin="0s"></animateTransform></svg>

HTML

<svg viewBox="0 0 300 300" xmlns="http://www.w3.org/2000/svg" xmlns:svg="http://www.w3.org/2000/svg">

 <defs id="defs">

  <radialGradient id="gr">

   <stop id="st1" offset="0" stop-color="#660000"/>

   <stop id="st2" offset="0.5" stop-color="#c30000"/>

   <stop id="st3" offset="1" stop-color="#a00000"/>

  </radialGradient>

 </defs>

 <g class="layer">

  <title>Layer 1</title>

  <circle cx="150" cy="150" fill="url(#gr)" id="iris" r="145" stroke="#000" stroke-width="10"/>

  <path d="m177.6,10.7c-42.6,57.7 -22.2,90 2.2,107.8c81.1,42.1 95,96 76.1,126.4c-18.6,-53 -57.9,-72.5 -97.4,-50c-71.6,43.7 -117.8,36.3 -142.8,1.7c42.5,6.5 93.4,-3.1 92.2,-68.3c1.6,-30.7 3.6,-111.7 69.7,-117.6z" fill="#000" id="tomoe"/>

  <circle cx="150" cy="150" fill="#a00000" id="center" r="20"/>

 </g>

<animateTransform attributeName="transform" type="rotate" repeatCount="indefinite" dur="1.5s" values="360;0" begin="0s"></animateTransform></svg>

и ответ чата гопоты: