.shiny-image {
    position: relative;
    display: inline-block;
    overflow: hidden;
}

.shiny-image img {
    display: block;
    width: 100%;
    height: auto;
}

.shiny-image::before {
    content: "";
    position: absolute;
    top: 0;

    /* 400px breit */
    width: 400px;
    height: 100%;

    /* Start komplett außerhalb */
    left: -450px;

    background: linear-gradient(
        to right,
        transparent,
        rgba(255,255,255,0.85),
        transparent
    );

    transform: skewX(-20deg);

    animation-name: shiny-cycle;
    animation-duration: var(--cycle-duration, 8s);
    animation-timing-func