SVG animation, CSS spin animation but stay on the same place

I am animating a propeller on my website.
http://bug.soulmates.company (See section 3)
But even though I set style to:

.propeller_spin {
   animation-name: spin;
   animation-duration: 4000ms;
   animation-iteration-count: infinite;
   transform-origin: center center;
 }

 @keyframes spin {
   from {
     transform:rotate(0deg);
     transform-origin: center center;
   }
   to {
     transform:rotate(360deg);
     transform-origin: center center;
   }
 }

The propeller doesn´t stay on it´s place while spinning.