.mibew{
    position: fixed;
    text-align: center;
    right: 10px;
    bottom: 10px;
    background: lightblue;
    z-index: 999;
    padding: 5px;
    padding-left:15px;
    padding-right:15px;
    border-radius: 50px;
    transition: .5s;
}

@keyframes mibewh4 {
     100% { opacity: 1; }
     50% { opacity: 0.5; }


 }
#mibewh4 {
   -webkit-animation: mibewh4 .95s linear infinite;
   -moz-animation: mibewh4 .95s linear infinite;
   -ms-animation: mibewh4 .95s linear infinite;
   -o-animation: mibewh4 .95s linear infinite;
   animation: mibewh4 .95s linear infinite;
}