onoff

    <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.1.0/css/all.css" integrity="sha384-lKuwvrZot6UHsBSfcMvOkWwlCMgc0TaWr+30HWe3a4ltaBwTZhyTEggF5tJv8tbt" crossorigin="anonymous">
    <style type="text/css">

    @keyframes fa-blink {
        0% { opacity: 1; }
        25% { opacity: 0.25; }
        50% { opacity: 0.5; }
        75% { opacity: 0.75; }
        100% { opacity: 0; }
    }
    .fa-blink {
        -webkit-animation: fa-blink 1.5s linear infinite;
        -moz-animation: fa-blink 1s linear infinite;
        -ms-animation: fa-blink 1s linear infinite;
        -o-animation: fa-blink 1s linear infinite;
        animation: fa-blink 1.5s linear infinite;
    }
    .green{
        color: green;
    }
    .red{
        color: red;
    }