/* Top nav bar - same as homepage */
    .bbs-nav-bar {
      display: flex; align-items: center;
      background: var(--ui-surface);
      border-bottom: 1px solid var(--ui-line);
      position: sticky; top: 0; z-index: 50;
      margin-bottom: var(--gap-xl);
      overflow-x: auto;
      -webkit-overflow-scrolling: touch;
    }
    .bbs-nav-tab {
      display: flex; align-items: center; gap: 8px;
      padding: 14px 20px; font-family: var(--font-mono);
      font-size: 0.72rem; font-weight: 500;
      color: var(--ui-fg-muted); cursor: pointer;
      border: none; background: none;
      border-bottom: 3px solid transparent;
      white-space: nowrap; letter-spacing: 0.04em;
      text-decoration: none;
      transition: all var(--dur-fast) var(--ease-out);
    }
    .bbs-nav-tab:hover { color: var(--ui-fg); background: var(--ui-overlay); }
    .bbs-nav-tab.active {
      color: var(--ui-fg); font-weight: 600;
      border-bottom-color: var(--ui-accent, #8b7cf7);
    }
    .bbs-nav-tab i { font-size: 0.85rem; }

    @media (max-width: 768px) {
      .bbs-nav-tab { padding: 12px 14px; font-size: 0.68rem; gap: 5px; }
      .bbs-nav-tab i { font-size: 0.75rem; }
    }
    @media (max-width: 480px) {
      .bbs-nav-tab { padding: 10px 12px; font-size: 0.62rem; }
    }