Template:Link/styles.css

Template page
.link-icon {
    margin-right: 4px;
    opacity: 0.3;
}

.link-icon img {
    margin-bottom: 2px;
    height: 14px;
    width: auto;
}

/* Dark mode */
@media (prefers-color-scheme: dark) {
    .link-icon img {
        filter: invert(1);
    }
}