@keyframes fa-blink {
     0% { opacity: 1; }
     50% { opacity: 0.5; }
     100% { opacity: 0; }
 }
.fa-blink {
   -webkit-animation: fa-blink .75s linear infinite;
   -moz-animation: fa-blink .75s linear infinite;
   -ms-animation: fa-blink .75s linear infinite;
   -o-animation: fa-blink .75s linear infinite;
   animation: fa-blink .75s linear infinite;
}