.gear {
  -webkit-animation: myanim 8s infinite; /* Safari 5, Chrome */
     -moz-animation: myanim 8s infinite; /* Firefox 5-15 */
       -o-animation: myanim 8s infinite; /* Opera 12+ */
          animation: myanim 8s infinite; /* Safari 5, Chrome, Firefox 16+ */
}

@-webkit-keyframes myanim {
  0%   { opacity: 1.0; }
  50%  { opacity: 0.5; }
  52%  { opacity: 0.3; }
  53%  { opacity: 0.5; }
  55%  { opacity: 0; }
  100% { opacity: 1.0; }
}
@-moz-keyframes myanim {
  0%   { opacity: 1.0; }
  50%  { opacity: 0.5; }
  52%  { opacity: 0.3; }
  53%  { opacity: 0.5; }
  55%  { opacity: 0; }
  100% { opacity: 1.0; }
}
@-o-keyframes myanim {
  0%   { opacity: 1.0; }
  50%  { opacity: 0.5; }
  52%  { opacity: 0.3; }
  53%  { opacity: 0.5; }
  55%  { opacity: 0; }
  100% { opacity: 1.0; }
}
@keyframes myanim {
  0%   { opacity: 1.0; }
  50%  { opacity: 0.5; }
  52%  { opacity: 0.3; }
  53%  { opacity: 0.5; }
  55%  { opacity: 0; }
  100% { opacity: 1.0; }
}