/* ── Hero ── */
    .hero {
        padding: 56px 0 48px;
        position: relative;
        overflow: hidden;
    }
    .hero-tag {
        display: inline-flex;
        align-items: center;
        gap: 10px;
        padding: 6px 14px 6px 8px;
        border: 1px solid var(--line);
        border-radius: 999px;
        font-size: 12.5px;
        color: var(--fg-mute);
        margin-bottom: 28px;
    }
    .hero-tag .dot {
        width: 7px; height: 7px;
        border-radius: 50%;
        background: var(--accent);
        box-shadow: 0 0 0 3px color-mix(in oklch, var(--accent) 20%, transparent);
        flex: none;
    }
    .hero-tag b { color: var(--fg); font-weight: 600; }
    .hero-tag .tag-v {
        font-family: var(--f-mono);
        font-size: 11px;
        padding: 2px 8px;
        background: var(--bg2);
        border-radius: 999px;
        letter-spacing: 0.04em;
    }

    .hero h1 {
        font-family: var(--f-display);
        font-weight: 700;
        font-size: clamp(52px, 8.2vw, 120px);
        line-height: 0.92;
        letter-spacing: -0.035em;
        margin: 0 0 28px;
        color: var(--fg);
    }
    .hero h1 em {
        font-style: normal;
        color: var(--accent);
    }
    .hero h1 .stroke {
        -webkit-text-stroke: 1.5px var(--fg);
        color: transparent;
        font-style: italic;
    }
    html[data-theme="light"] .hero h1 .stroke {
        -webkit-text-stroke: 1.5px var(--fg);
    }

    .hero-lede {
        font-size: 17px;
        line-height: 1.55;
        color: var(--fg-mute);
        margin: 0 0 36px;
    }

    /* ── Search field ── */
    .sf-wrap { margin-top: 4px; display: flex; align-items: center; gap: 10px; }
    .sf-wrap .sf { flex: 1; min-width: 0; }
    .sf {
        background: var(--bg2);
        border: 1px solid var(--line);
        border-radius: 16px;
        padding: 8px;
    }
    .sf-row {
        display: grid;
        grid-template-columns: 1.5fr 1px 1.2fr 1px 1fr auto;
        align-items: stretch;
        gap: 0;
    }
    .sf-field {
        display: flex;
        flex-direction: column;
        justify-content: center;
        padding: 10px 16px;
        min-width: 0;
    }
    .sf-label {
        font-family: var(--f-mono);
        font-size: 10px;
        letter-spacing: 0.14em;
        color: var(--fg-dim);
        margin-bottom: 4px;
        text-transform: uppercase;
    }
    .sf-input {
        background: transparent;
        border: none;
        outline: none;
        color: var(--fg);
        font: 600 15px var(--f-body);
        padding: 0;
        width: 100%;
        min-width: 0;
        appearance: none;
        -webkit-appearance: none;
    }
    .sf-input::placeholder { color: var(--fg-dim); font-weight: 500; }
    .sf-input option { background: var(--bg2); color: var(--fg); }
    .sf-divider {
        background: var(--line);
        width: 1px;
        align-self: stretch;
        margin: 8px 0;
    }
    .sf-btn {
        display: inline-flex;
        align-items: center;
        gap: 8px;
        background: var(--accent);
        color: var(--accent-ink);
        border: none;
        border-radius: 12px;
        padding: 0 22px;
        font: 700 14px var(--f-body);
        cursor: pointer;
        white-space: nowrap;
        text-decoration: none;
        transition: transform .15s ease, opacity .15s;
    }
    .sf-btn:hover { transform: translateY(-1px); opacity: 0.9; color: var(--accent-ink); }
    .sf-btn.sf-btn--ghost {
        background: var(--bg2);
        color: var(--fg-mute);
        border: 1px solid var(--line);
        margin-left: 0;
        align-self: stretch;
    }
    .sf-btn.sf-btn--ghost:hover { background: var(--bg3); color: var(--fg); border-color: var(--fg-dim); transform: translateY(-1px); }

    @media (max-width: 768px) {
        .sf-row {
            grid-template-columns: 1fr;
            gap: 0;
        }
        .sf-wrap { flex-direction: column; align-items: stretch; }
        .sf-divider { width: 100%; height: 1px; margin: 0; }
        .sf-btn { margin: 0; padding: 14px 22px; justify-content: center; }
    }

    @media (max-width: 768px) {
        .hero h1 { margin-bottom: 20px; }
    }

    /* ── Browse by discipline ── */
    .home-section {
        padding: 80px 0 0;
    }
    .home-section-head {
        display: flex;
        justify-content: space-between;
        align-items: flex-end;
        margin-bottom: 36px;
        gap: 32px;
    }
    .home-eyebrow {
        display: block;
        font-family: var(--f-mono);
        font-size: 11px;
        letter-spacing: 0.12em;
        text-transform: uppercase;
        color: var(--fg-mute);
        font-weight: 500;
        margin-bottom: 14px;
    }
    .home-section-h2 {
        font-family: var(--f-display);
        font-weight: 700;
        font-size: clamp(32px, 3.6vw, 52px);
        letter-spacing: -0.03em;
        line-height: 1;
        margin: 0;
        color: var(--fg);
    }
    .home-cats {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
        gap: 10px;
    }
    .home-cat-tile {
        position: relative;
        padding: 22px 20px 26px;
        background: var(--bg2);
        border: 1px solid var(--line-soft);
        border-radius: 12px;
        transition: all .2s ease;
        overflow: hidden;
        min-height: 170px;
        display: flex;
        flex-direction: column;
        justify-content: space-between;
        text-decoration: none;
        color: var(--fg);
    }
    .home-cat-tile:hover {
        background: var(--bg3);
        border-color: var(--accent);
        transform: translateY(-3px);
        color: var(--fg);
    }
    .home-cat-tile:hover .home-cat-arrow { color: var(--accent); transform: translate(4px, -4px); }
    .home-cat-arrow {
        display: block;
        text-align: right;
        font-size: 18px;
        color: var(--fg-dim);
        transition: transform .2s, color .2s;
        margin-bottom: 10px;
    }
    .home-cat-name {
        font-family: var(--f-display);
        font-weight: 700;
        font-size: 26px;
        letter-spacing: -0.02em;
        line-height: 1.1;
    }
    .home-cat-count {
        font-family: var(--f-mono);
        font-size: 11px;
        color: var(--fg-mute);
        letter-spacing: 0.08em;
        margin-top: 6px;
    }
    .home-cat-subs {
        margin-top: 18px;
        display: flex;
        flex-wrap: wrap;
        gap: 4px;
    }
    .home-cat-subs span {
        font-family: var(--f-mono);
        font-size: 10.5px;
        color: var(--fg-dim);
        padding: 2px 6px;
        border-radius: 3px;
        background: var(--bg);
        letter-spacing: 0.04em;
    }
    .home-sub-group {
        margin-top: 24px;
    }
    .home-sub-group-label {
        font-family: var(--f-mono);
        font-size: 10.5px;
        letter-spacing: 0.12em;
        text-transform: uppercase;
        color: var(--fg-dim);
        margin-bottom: 8px;
    }
    .home-sub-tiles {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
        gap: 8px;
    }
    .home-sub-tile {
        display: flex;
        flex-direction: column;
        justify-content: space-between;
        padding: 16px 16px 14px;
        background: var(--bg2);
        border: 1px solid var(--line-soft);
        border-radius: 10px;
        text-decoration: none;
        color: var(--fg);
        min-height: 90px;
        transition: all .2s ease;
    }
    .home-sub-tile:hover {
        background: var(--bg3);
        border-color: var(--accent);
        transform: translateY(-2px);
        color: var(--fg);
    }
    .home-sub-tile:hover .home-sub-tile-arrow { color: var(--accent); transform: translate(3px, -3px); }
    .home-sub-tile-arrow {
        display: block;
        text-align: right;
        font-size: 14px;
        color: var(--fg-dim);
        transition: transform .2s, color .2s;
        margin-bottom: 8px;
    }
    .home-sub-tile-name {
        font-family: var(--f-display);
        font-weight: 700;
        font-size: 17px;
        letter-spacing: -0.02em;
        line-height: 1.15;
    }
    .home-cat-parent-label {
        font-family: var(--f-mono);
        font-size: 10px;
        letter-spacing: 0.12em;
        text-transform: uppercase;
        color: var(--fg-dim);
        margin-bottom: 4px;
    }

    @media (max-width: 768px) {
        .home-cats { grid-template-columns: repeat(2, 1fr); }
        .home-sub-tiles { grid-template-columns: repeat(2, 1fr); }
    }

    /* ── Keep existing sections working ── */
    .category-card {
        background: var(--bg2);
        border: 1px solid var(--line-soft);
        border-radius: 12px;
        padding: 28px 20px;
        text-align: center;
        text-decoration: none;
        color: var(--fg);
        transition: transform 0.2s, border-color 0.2s, background 0.2s;
        display: block;
    }
    .category-card:hover {
        transform: translateY(-4px);
        border-color: var(--accent);
        background: var(--bg3);
        color: var(--fg);
    }
    .category-icon-wrap { height: 75px; display: flex; align-items: center; justify-content: center; margin-bottom: 10px; }
    .category-card i { font-size: 2.2rem; color: var(--accent); }
    .category-icon { width: 75px; height: 75px; object-fit: contain; }
    .section-title { font-weight: 700; font-size: 1.4rem; color: var(--fg); font-family: var(--f-display); letter-spacing: -0.02em; }