.activity-hub { max-width: 1120px; min-height: 68vh; margin: 22px auto 42px; padding: 0 14px 64px; }
.activity-context {
    margin: 18px 0 18px; background: var(--surf,#fff); border: 1px solid var(--brd,#e2e8f0);
    border-radius: 16px; padding: 18px; color: var(--txt-2,#475569); line-height: 1.7;
    box-shadow: 0 4px 18px rgba(15,23,42,.04);
}
.activity-context h2 { margin: 0 0 8px; color: var(--txt,#0f172a); font-size: 1.05rem; font-weight: 800; }
.activity-context p { margin: 0 0 10px; font-size: .9rem; }
.activity-context-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; margin-top: 12px; }
.activity-context-card {
    background: var(--surf2,#f8fafc); border: 1px solid var(--brd,#e2e8f0);
    border-radius: 12px; padding: 12px; min-width: 0;
}
.activity-context-card strong { display: block; color: var(--txt,#0f172a); font-size: .86rem; margin-bottom: 4px; }
.activity-context-card span { display: block; font-size: .8rem; line-height: 1.55; color: var(--txt-2,#64748b); }
.activity-toolbar { margin: 18px 0; display: flex; gap: 12px; align-items: center; }
.activity-search {
    width: 280px; min-height: 42px; border: 1px solid var(--brd,#e2e8f0);
    background: var(--surf,#fff); color: var(--txt,#0f172a); border-radius: 14px;
    padding: 0 15px; font: inherit; flex-shrink: 0;
}
.activity-count { color: var(--txt-2,#64748b); font-size: .9rem; font-weight: 700; white-space: nowrap; }
.activity-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
.activity-card {
    display: flex; flex-direction: column; gap: 13px; min-height: 205px;
    background: var(--surf,#fff); border: 1px solid var(--brd,#e2e8f0);
    border-radius: 18px; padding: 15px; text-decoration: none; color: inherit;
    box-shadow: 0 4px 18px rgba(15,23,42,.06);
    transition: transform .16s ease, box-shadow .16s ease, border-color .16s ease;
}
.activity-card:hover { transform: translateY(-3px); box-shadow: 0 18px 42px rgba(15,23,42,.12); border-color: rgba(37,99,235,.34); }
.activity-icon {
    width: 46px; height: 46px; display: grid; place-items: center; border-radius: 15px;
    background: rgba(37,99,235,.1); color: var(--c-primary,#2563eb); font-size: 1.02rem;
}
.activity-card-top { display: flex; align-items: flex-start; justify-content: space-between; gap: 10px; }
.activity-section {
    display: inline-flex; align-items: center; min-height: 25px; max-width: 145px; border-radius: 999px;
    padding: 0 9px; background: rgba(37,99,235,.08); color: var(--c-primary,#2563eb);
    font-size: .66rem; line-height: 1.15; font-weight: 800; text-align: right;
}
.activity-card h2 { margin: 0; color: var(--txt,#0f172a); font-size: .98rem; line-height: 1.25; letter-spacing: 0; }
.activity-card p { margin: 0; color: var(--txt-2,#64748b); font-size: .84rem; line-height: 1.5; }
.activity-open {
    margin-top: auto; min-height: 38px; border-radius: 12px; display: inline-flex; align-items: center; justify-content: center;
    gap: 7px; font-weight: 800; font-size: .84rem; text-decoration: none; background: var(--c-primary,#2563eb); color: #fff;
}
.activity-empty {
    background: var(--surf,#fff); border: 1px solid var(--brd,#e2e8f0); border-radius: 18px;
    padding: 34px; color: var(--txt-2,#64748b); text-align: center;
}
[data-theme="dark"] .activity-card,
[data-theme="dark"] .activity-search,
[data-theme="dark"] .activity-empty,
[data-theme="dark"] .activity-context { background: var(--surf,#111f3a); border-color: var(--brd,rgba(255,255,255,.08)); }
[data-theme="dark"] .activity-context-card { background: var(--surf2,#172542); border-color: var(--brd,rgba(255,255,255,.08)); }
[data-theme="dark"] .activity-icon { background: rgba(96,165,250,.14); color: #93c5fd; }
[data-theme="dark"] .activity-section { background: rgba(96,165,250,.13); color: #bfdbfe; }
@media (max-width: 1080px) { .activity-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (max-width: 820px) { .activity-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 620px) {
    .activity-toolbar { flex-direction: column; align-items: stretch; }
    .activity-search { width: 100%; }
    .activity-context-grid { grid-template-columns: 1fr; }
    .activity-grid { grid-template-columns: 1fr; }
}