Control-Center/frontend/src/app/pages/hub/hub-page.component.scss

// ============================================================================
// Hub Page — Responsive AgentCard Grid with Filter Chips
// Per CUB-27 spec breakpoints:
//   Compact  (0–599px):  Single-column cards, horizontal-scroll filter chips
//   Medium   (600–1023px): 2-column grid
//   Expanded (≥1024px): 3+ column auto-fill grid
// ============================================================================

.hub-page {
  display: flex;
  flex-direction: column;
  gap: 16px;
  min-height: 400px;
  overflow-x: hidden;
}

.hub-page__title {
  grid-column: 1 / -1;
  font-size: 24px;
  font-weight: 600;
  color: var(--cc-on-surface);
  margin: 0 0 8px;
}

// ---------------------------------------------------------------------------
// Filter Chip Group
// ---------------------------------------------------------------------------
.hub-page__filters {
  display: flex;
  gap: 8px;
  padding: 4px 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none; // Firefox

  &::-webkit-scrollbar {
    display: none; // Chrome/Safari
  }
}

.hub-page__filter-chip {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 36px;
  min-width: 48px; // Touch target
  padding: 6px 16px;
  border: 1px solid var(--cc-outline);
  border-radius: 20px;
  background-color: transparent;
  color: var(--cc-on-surface-variant);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  cursor: pointer;
  white-space: nowrap;
  transition: background-color 150ms ease, color 150ms ease, border-color 150ms ease;
  flex-shrink: 0; // Prevent shrinking in scroll container

  &:hover {
    background-color: rgba(255, 255, 255, 0.06);
    color: var(--cc-on-surface);
  }

  &:focus-visible {
    outline: 2px solid var(--status-active);
    outline-offset: 2px;
  }

  &--active {
    background-color: var(--status-active-bg);
    color: var(--status-active);
    border-color: var(--status-active);
  }
}

// ---------------------------------------------------------------------------
// Agent Card Grid
// ---------------------------------------------------------------------------
.hub-page__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--cc-card-gap);
}

// ---------------------------------------------------------------------------
// Empty State
// ---------------------------------------------------------------------------
.hub-page__placeholder,
.hub-page__empty {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 48px 24px;
  color: var(--cc-on-surface-variant);
  font-size: 16px;
  text-align: center;
}

// ---------------------------------------------------------------------------
// Compact (0–599px): Single-column cards
// ---------------------------------------------------------------------------
@media (max-width: 599px) {
  .hub-page {
    padding: 0;
  }

  .hub-page__grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .hub-page__filters {
    padding: 4px 0 8px;
    // Ensure horizontal scroll on mobile
    margin: 0 -8px;
    padding-left: 8px;
    padding-right: 8px;
  }
}

// ---------------------------------------------------------------------------
// Medium (600–1023px): 2-column grid
// ---------------------------------------------------------------------------
@media (min-width: 600px) and (max-width: 1023px) {
  .hub-page__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--cc-card-gap);
  }
}

// ---------------------------------------------------------------------------
// Expanded (≥1024px): 3+ column auto-fill grid
// ---------------------------------------------------------------------------
@media (min-width: 1024px) {
  .hub-page__grid {
    grid-template-columns: repeat(auto-fill, minmax(var(--cc-card-min-width), 1fr));
    gap: var(--cc-card-gap);
  }
}