.headeralert {
  font-size:28px;
  font-family:helvetica;
  font-weight:bold;
  color:#FF0000;
  text-transform:uppercase;
  position: absolute;
  margin-left: -750px;
  margin-top: 15px;
}
.parpadea {
  
  animation-name: parpadeo;
  animation-duration: 1s;
  animation-timing-function: linear;
  animation-iteration-count: infinite;

  -webkit-animation-name:parpadeo;
  -webkit-animation-duration: 1s;
  -webkit-animation-timing-function: linear;
  -webkit-animation-iteration-count: infinite;
}

@-moz-keyframes parpadeo{  
  0% { opacity: 1.0; }
  50% { opacity: 0.0; }
  100% { opacity: 1.0; }
}

@-webkit-keyframes parpadeo {  
  0% { opacity: 1.0; }
  50% { opacity: 0.0; }
   100% { opacity: 1.0; }
}

@keyframes parpadeo {  
  0% { opacity: 1.0; }
   50% { opacity: 0.0; }
  100% { opacity: 1.0; }
}