@-webkit-keyframes pulse {
    0% {
        opacity: 0;
        background-position: center top;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
    10% {
        opacity: 0;
    }
    50% {
        opacity: 1;
        -moz-background-size: 75% auto;
        -o-background-size: 75% auto;
        -webkit-background-size: 75% auto;
        background-size: 75% auto;
    }
    90% {
        opacity: 0;
    }
    100% {
        opacity: 0;
        background-position: center bottom;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
}
@-moz-keyframes pulse {
    0% {
        opacity: 0;
        background-position: center top;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
    10% {
        opacity: 0;
    }
    50% {
        opacity: 1;
        -moz-background-size: 75% auto;
        -o-background-size: 75% auto;
        -webkit-background-size: 75% auto;
        background-size: 75% auto;
    }
    90% {
        opacity: 0;
    }
    100% {
        opacity: 0;
        background-position: center bottom;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
}
@-ms-keyframes pulse {
    0% {
        opacity: 0;
        background-position: center top;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
    10% {
        opacity: 0;
    }
    50% {
        opacity: 1;
        -moz-background-size: 75% auto;
        -o-background-size: 75% auto;
        -webkit-background-size: 75% auto;
        background-size: 75% auto;
    }
    90% {
        opacity: 0;
    }
    100% {
        opacity: 0;
        background-position: center bottom;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
}
@keyframes pulse {
    0% {
        opacity: 0;
        background-position: center top;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
    10% {
        opacity: 0;
    }
    50% {
        opacity: 1;
        -moz-background-size: 75% auto;
        -o-background-size: 75% auto;
        -webkit-background-size: 75% auto;
        background-size: 75% auto;
    }
    90% {
        opacity: 0;
    }
    100% {
        opacity: 0;
        background-position: center bottom;
        -moz-background-size: 0 auto;
        -o-background-size: 0 auto;
        -webkit-background-size: 0 auto;
        background-size: 0 auto;
    }
}

.scroll-down {
    z-index: 999;
    margin: 0;
    -moz-border-radius: 100px;
    -webkit-border-radius: 100px;
    border-radius: 100px;
    position: absolute;
    left: 50%;
    bottom: 50px;
    width: 100px;
    height: 100px;
    margin-left: -50px;
    margin-top: -50px;
}
.scroll-down a {
    display: block;
    opacity: 0;
    -moz-border-radius: 100px;
    -webkit-border-radius: 100px;
    border-radius: 100px;
    -moz-transition: all 0.4s ease;
    -o-transition: all 0.4s ease;
    -webkit-transition: all 0.4s ease;
    transition: all 0.4s ease;
    line-height: 0;
    font-size: 0;
    color: transparent;
    margin-left: auto;
    margin-right: auto;
    width: 100%;
    height: 100%;
    -moz-background-size: 0 auto;
    -o-background-size: 0 auto;
    -webkit-background-size: 0 auto;
    background-size: 0 auto;
    -webkit-animation: pulse 1.5s 0s infinite normal ease forwards;
    -moz-animation: pulse 1.5s 0s infinite normal ease forwards;
    -o-animation: pulse 1.5s 0s infinite normal ease forwards;
    animation: pulse 1.5s 0s infinite normal ease forwards;
    background-image: url("http://jamesmuspratt.com/codepen/img/arrow-down.svg");
    background-repeat: no-repeat;
}
.scroll-down a:before, .scroll-down a:after {
    content: " ";
    position: absolute;
    top: 0;
    left: 0;
    display: block;
    width: 100%;
    height: 100%;
    background: url("http://jamesmuspratt.com/codepen/img/arrow-down.svg") no-repeat center top;
    -moz-background-size: 100% auto;
    -o-background-size: 100% auto;
    -webkit-background-size: 100% auto;
    background-size: 100% auto;
}
.scroll-down a:before {
    -webkit-animation: pulse 1.5s 0.25s infinite normal ease forwards;
    -moz-animation: pulse 1.5s 0.25s infinite normal ease forwards;
    -o-animation: pulse 1.5s 0.25s infinite normal ease forwards;
    animation: pulse 1.5s 0.25s infinite normal ease forwards;
}
.scroll-down a:after {
    -webkit-animation: pulse 1.5s 0.5s infinite normal ease forwards;
    -moz-animation: pulse 1.5s 0.5s infinite normal ease forwards;
    -o-animation: pulse 1.5s 0.5s infinite normal ease forwards;
    animation: pulse 1.5s 0.5s infinite normal ease forwards;
}
.scroll-down a:hover {
    background-color: rgba(0, 0, 0, 0.3);
}