As King King said, you must add the browser specific prefix. This should cover most browsers:
@keyframes flickerAnimation {
0% { opacity:1; }
50% { opacity:0; }
100% { opacity:1; }
}
@-o-keyframes flickerAnimation{
0% { opacity:1; }
50% { opacity:0; }
100% { opacity:1; }
}
@-moz-keyframes flickerAnimation{
0% { opacity:1; }
50% { opacity:0; }
100% { opacity:1; }
}
@-webkit-keyframes flickerAnimation{
0% { opacity:1; }
50% { opacity:0; }
100% { opacity:1; }
}
.animate-flicker {
-webkit-animation: flickerAnimation 1s infinite;
-moz-animation: flickerAnimation 1s infinite;
-o-animation: flickerAnimation 1s infinite;
animation: flickerAnimation 1s infinite;
}
<div class="animate-flicker">Loading...</div>