Template:SwitchImage/style.css

.themed-image-container {
    display: inline-block;
    line-height: 0;
}

.themed-image-dark {
    display: none;
}

html.client-dark-mode .themed-image-light {
    display: none;
}

html.client-dark-mode .themed-image-dark {
    display: block;
}

@media (prefers-color-scheme: dark) {
    html.client-js:not(.client-light-mode) .themed-image-light {
        display: none;
    }
    html.client-js:not(.client-light-mode) .themed-image-dark {
        display: block;
    }
}