.snow {
    background: none;
    font-family: Androgyne;
    background-image: url('../img/s1.png'), url('../img/s2.png'), url('../img/s3.png');
    height: 100%;
    left: 0;
    position: absolute;
    top: 0;
    width: 100%;
    z-index: 0;
    -webkit-animation: snow 10s linear infinite;
    -moz-animation: snow 10s linear infinite;
    -ms-animation: snow 10s linear infinite;
    animation: snow 10s linear infinite;
}

@keyframes snow {
    0% {
        background-position: 0px 0px, 0px 0px, 0px 0px;
    }
    50% {
        background-position: 500px 500px, 100px 200px, -100px 150px;
    }
    100% {
        background-position: 500px 1000px, 200px 400px, -100px 300px;
    }
}

@-moz-keyframes snow {
    0% {
        background-position: 0px 0px, 0px 0px, 0px 0px;
    }
    50% {
        background-position: 500px 500px, 100px 200px, -100px 150px;
    }
    100% {
        background-position: 400px 1000px, 200px 400px, 100px 300px;
    }
}

@-webkit-keyframes snow {
    0% {
        background-position: 0px 0px, 0px 0px, 0px 0px;
    }
    50% {
        background-position: 500px 500px, 100px 200px, -100px 150px;
    }
    100% {
        background-position: 500px 1000px, 200px 400px, -100px 300px;
    }
}

@-ms-keyframes snow {
    0% {
        background-position: 0px 0px, 0px 0px, 0px 0px;
    }
    50% {
        background-position: 500px 500px, 100px 200px, -100px 150px;
    }
    100% {
        background-position: 500px 1000px, 200px 400px, -100px 300px;
    }
}