CSS blink class

@keyframes blink {
    50% { opacity:0.0  }
}
@-webkit-keyframes blink {
    50% { opacity:0.0  }
}
@-moz-keyframes blink {
    50% { opacity:0.0  }
}
@-ms-keyframes blink {
    50% { opacity:0.0  }
}
@-o-keyframes blink {
    50% { opacity:0.0  }
}
.blink {
    -webkit-animation: blink 1s step-start 0s infinite;
    -moz-animation: blink 1s step-start 0s infinite;
    -ms-animation: blink 1s step-start 0s infinite;
    -o-animation: blink 1s step-start 0s infinite;
    animation: blink 1s step-start 0s infinite;
}