#float_message[class*="up"] .message_title::before {
    content: '\e635';
    font-family: 'iconfont'; 
    vertical-align: middle;
    font-size: 28px;
    color: #fff;
    animation: breath 2s infinite ease-in-out;
}
@keyframes breath {
    0% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.4;
        transform: scale(1.1);
        font-size: 20px;
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}