/* v13.1 — knowledge index and article detail */
.resource-hero--knowledge::after {
    background: linear-gradient(90deg, rgba(17,17,17, .97) 4%, rgba(17,17,17, .76) 52%, rgba(17,17,17, .3));
}
.resource-hero--knowledge .eyebrow,
.article-hero .eyebrow { color: var(--brand-bright); }

.resource-filters a { transition: color .25s, background .25s, border-color .25s, transform .25s var(--ease); }
.resource-filters a:hover { transform: translateY(-2px); }
.resource-filters a:focus-visible { outline: 3px solid rgba(0,0,0, .35); outline-offset: 3px; }

.knowledge-feature { position: relative; border-top: 4px solid var(--accent); }
.knowledge-feature::after {
    content: "精选";
    position: absolute;
    top: 24px;
    left: 24px;
    z-index: 2;
    padding: 8px 12px;
    color: white;
    background: var(--ink);
    font-size: 11px;
    font-weight: 800;
    letter-spacing: .12em;
}
.knowledge-feature:focus-visible,
.knowledge-card a:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }

.knowledge-card {
    border: 1px solid rgba(0,0,0, .08);
    box-shadow: 0 12px 34px rgba(0,0,0, .06);
    transition: transform .35s var(--ease), box-shadow .35s var(--ease);
}
.knowledge-card:hover { transform: translateY(-6px); box-shadow: 0 22px 50px rgba(0,0,0, .12); }

.article-hero { position: relative; overflow: hidden; }
.article-hero::after {
    content: "KNOWLEDGE";
    position: absolute;
    right: -24px;
    bottom: -34px;
    color: rgba(255, 255, 255, .035);
    font-size: clamp(70px, 14vw, 190px);
    font-weight: 900;
    letter-spacing: -.06em;
    pointer-events: none;
}
.article-hero__inner { position: relative; z-index: 1; }
.article-body { font-size: 17px; }
.article-body p:first-child::first-letter {
    float: left;
    margin: 8px 10px 0 0;
    color: var(--accent);
    font-size: 58px;
    font-weight: 800;
    line-height: .75;
}
.article-aside { border-top: 4px solid var(--accent); box-shadow: 0 20px 54px rgba(0,0,0, .1); }

@media (max-width: 640px) {
    .knowledge-feature::after { top: 16px; left: 16px; }
    .article-hero::after { display: none; }
    .article-body { font-size: 16px; }
}

/* v13.11: component colors and keyboard states. */
.resource-hero--knowledge::after { background: linear-gradient(90deg, rgba(17,17,17,.72) 4%, rgba(17,17,17,.46) 52%, rgba(17,17,17,.14)); }
.resource-hero--knowledge .resource-hero__inner { text-shadow: 0 2px 5px rgba(0,0,0,.65); }
.knowledge-index .resource-filters a:hover,
.knowledge-index .resource-filters a:focus-visible,
.knowledge-index .resource-filters a.is-active,
.knowledge-index .resource-empty .button--dark { background: var(--accent-text); border-color: var(--accent-text); color: #fff; }
.knowledge-index .resource-empty .button--dark:hover { background: var(--accent-deep); }