.back-to-top {
    background-color: #00D2AA;
    position: fixed;
    bottom: 3em;
    right: 3em;
    border-radius: 1em;
    padding: 1em;
    box-shadow: 0.2em 0.5em 0.8em 0 rgba(0, 0, 0, 0.3);
    transition: bottom 0.5s;
    animation-delay: 2s;
    animation-iteration-count: infinite;
}

.back-to-top:hover {
    background-color: darkgray;
    bottom: 3.5em;
}

.back-to-top img {
    padding: 0 0.3em;
}