#zalo-icon {
    position: fixed;
    bottom: 160px;
    left: 15px;
    width: 40px;
    height: auto;
    z-index: 9;
    animation: mes 2s .8s linear infinite;
    -webkit-animation: mes 2s .8s linear infinite;
}

#zalo-icon:after {
    content: "";
    display: block;
    position: absolute;
    width: 0;
    height: 0;
    border-radius: 100%;
    z-index: -1;
    border: solid 8px rgba(2, 144, 227, 0.707);
    padding: 40%;
    -webkit-box-sizing: content-box;
    box-sizing: content-box;
    left: 50%;
    top: 50%;
    -webkit-transform: translateX(-50%) translateY(-50%);
    -ms-transform: translateX(-50%) translateY(-50%);
    transform: translateX(-50%) translateY(-50%);
    -webkit-animation: mespad 4s .8s linear infinite;
    animation: mespad 4s .8s linear infinite;
}

@-webkit-keyframes mes {
    0% {
        -webkit-transform: rotateZ(0);
        transform: rotateZ(0);
    }

    5% {
        -webkit-transform: rotateZ(20deg);
        transform: rotateZ(20deg);
    }

    10% {
        -webkit-transform: rotateZ(-20deg);
        transform: rotateZ(-20deg);
    }

    15% {
        -webkit-transform: rotateZ(20deg);
        transform: rotateZ(20deg);
    }

    20% {
        -webkit-transform: rotateZ(-20deg);
        transform: rotateZ(-20deg);
    }

    25% {
        -webkit-transform: rotateZ(0);
        transform: rotateZ(0);
    }

    100% {
        -webkit-transform: rotateZ(0);
        transform: rotateZ(0);
    }
}

@keyframes mes {
    0% {
        -webkit-transform: rotateZ(0);
        transform: rotateZ(0);
    }

    5% {
        -webkit-transform: rotateZ(20deg);
        transform: rotateZ(20deg);
    }

    10% {
        -webkit-transform: rotateZ(-20deg);
        transform: rotateZ(-20deg);
    }

    15% {
        -webkit-transform: rotateZ(20deg);
        transform: rotateZ(20deg);
    }

    20% {
        -webkit-transform: rotateZ(-20deg);
        transform: rotateZ(-20deg);
    }

    25% {
        -webkit-transform: rotateZ(0);
        transform: rotateZ(0);
    }

    100% {
        -webkit-transform: rotateZ(0);
        transform: rotateZ(0);
    }
}

@-webkit-keyframes mespad {
    0% {
        padding: 35%;
        opacity: 1;
        border-width: 8px;
    }

    20% {
        padding: 50%;
        opacity: 1;
    }

    40% {
        padding: 65%;
    }

    60% {
        padding: 80%;
        opacity: 0.4;
        border-width: 0px;
    }

    100% {
        padding: 80%;
        opacity: 0.4;
        border-width: 0px;
    }
}

@keyframes mespad {
    0% {
        padding: 35%;
        opacity: 1;
        border-width: 8px;
    }

    20% {
        padding: 50%;
        opacity: 1;
    }

    40% {
        padding: 65%;
    }

    60% {
        padding: 80%;
        opacity: 0.4;
        border-width: 0px;
    }

    100% {
        padding: 80%;
        opacity: 0.4;
        border-width: 0px;
    }
}