svg animateTransform example

<svg
  width="120"
  height="120"
  viewBox="0 0 120 120"
  xmlns="http://www.w3.org/2000/svg">
  <style>
        polygon:nth-of-type(2) {opacity:.7;}
  </style>
  <polygon points="60,30 90,90 30,90" fill="maroon">
    <animateTransform
      attributeName="transform"
      type="rotate"
      from="0 60 70"
      to="360 60 70"
      dur="5s"
      repeatCount="indefinite" />
  </polygon>
  <polygon points="30,30 60,90 90,30" fill="skyblue">
    <animateTransform
      attributeName="transform"
      type="rotate"
      from="0 60 70"
      to="360 60 70"
      dur="5s"
      repeatCount="indefinite" />
  </polygon>
</svg>