/* wrapper */
.box {
    position:relative;
    width:500px; height:500px;
    overflow:hidden;
    border-radius:20px;
    background:#fff;
    box-shadow:20px 20px 60px #d9d9d9, -20px -20px 60px #fff;
}

/* follower element */
.follower {
    /* positioning */
    position:absolute; top:50%; left:50%;
    transform:translate(-50%, -50%);

    /* decorative */
    width:100px; height:100px; border-radius:50%;
    background-color:#1c1c1c; color:#fff;

    /* avoid transition conflict with GSAP */
    transition:none;

    /* sometimes you need this to avoid hovering flicker */
    pointer-events:none;
}