.mouse {
    font-size: 15px;
    width: 2em;
    height: 3em;
    border: 0.3em solid #fff;
    border-radius: 1em;
}

.mouse::after {
    content: "";
    display: block;
    width: 0.3em;
    height: 0.5em;
    margin-left: 0.55em;
    margin-top: 0.5em;
    background-color: #fff;
    border-radius: 0.15em;

    animation-name: movement;
    animation-duration: 2s;
    animation-iteration-count: infinite;
    animation-delay: 2s;
}

.mouse:hover::after {
    animation-play-state: paused;
}

@keyframes movement {
    0% {
        margin-top: 0.5em;
        opacity: 1;
    }
    50% {
        opacity: 1;
    }
    100% {
        margin-top: 1.5em;
        opacity: 0;
    }
}