Common.css

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/* CSS placed here will be applied to all skins */
/* ---- Feed block ---- */
.feed-block {
    margin: 2em 0;
}
.feed-title, .feed-title a {
    font-size: 1.4em;
    margin-bottom: 0.5em;
    color: inherit;
    text-decoration: none;
}
.feed-title a:hover {
    text-decoration: underline;
}

.feed-items {
    display: flex;
    flex-wrap: wrap;
    gap: 1em;
}

/* Individual card */
.feed-item {
    flex: 1 1 300px;
    max-width: 32%;
    box-sizing: border-box;
}
.feed-item-link {
    display: block;
    text-decoration: none;
    color: inherit;
}
.feed-item-thumb {
    height: 180px;
    background-size: cover;
    background-position: center;
    position: relative;
    border-radius: 6px;
    overflow: hidden;
}
.feed-item-title {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(transparent, rgba(0,0,0,0.75));
    padding: 0.5em 0.75em;
}
.feed-item-title h3 {
    color: #fff;
    margin: 0;
    font-size: 1.1em;
}
.feed-item-desc {
    margin-top: 0.5em;
    font-size: 0.9em;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.feed-item-more {
    color: #0645ad;
    font-weight: bold;
    margin-left: 0.3em;
}

/* Preview mode (homepage): force max 3 per row on wide screens */
.feed-mode-preview .feed-item {
    max-width: 32%;
}

/* Full mode (dedicated "view all" page) */
.feed-mode-full .feed-item {
    max-width: 32%;
}
/* Optional single-column layout: wrap a feed in <div class="feed-single"> */
.feed-single .feed-item {
    max-width: 100%;
    flex: 1 1 100%;
}

/* ---- Responsive breakpoints ---- */
@media (max-width: 900px) {
    .feed-item { max-width: 48%; }
}
@media (max-width: 600px) {
    .feed-items { flex-direction: column; }
    .feed-item { max-width: 100%; }
}

MediaWiki

Common.css