* { margin: 0; padding: 0; box-sizing: border-box; }
    body {
      font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
      background: #030a1a;
      color: #e2e8f0;
      overflow: hidden;
    }

    canvas#starfield {
      position: fixed; top: 0; left: 0; z-index: 1; display: block;
    }

    #topbar {
      position: fixed; top: 0; left: 0; right: 0; height: 60px; z-index: 20;
      background: linear-gradient(to bottom, rgba(4,12,28,0.98), rgba(4,12,28,0.9));
      border-bottom: 1px solid rgba(255,255,255,0.08);
      display: flex; align-items: center; gap: 20px; padding: 0 20px;
    }
    #topbar-title { font-size: 18px; font-weight: 600; color: #a78bfa; min-width: 200px; }
    #topbar-search {
      flex: 1; max-width: 300px;
      background: rgba(255,255,255,0.05); border: 1px solid rgba(255,255,255,0.1);
      color: #e2e8f0; padding: 8px 12px; border-radius: 6px; font-size: 14px;
    }
    #topbar-search::placeholder { color: rgba(255,255,255,0.4); }
    .topbar-btn-group { display: flex; gap: 8px; }
    .topbar-btn {
      background: rgba(255,255,255,0.08); border: 1px solid rgba(255,255,255,0.1);
      color: #e2e8f0; padding: 6px 12px; border-radius: 5px; font-size: 12px; cursor: pointer;
      transition: all 0.2s ease;
    }
    .topbar-btn:hover { background: rgba(255,255,255,0.12); border-color: rgba(255,255,255,0.2); }
    .topbar-btn.hidden { display: none; }
    #topbar-right { display: flex; gap: 8px; margin-left: auto; }
    #btn-feedback { background: rgba(52,211,153,0.12); border-color: rgba(52,211,153,0.35); color: #34d399; text-decoration: none; display: flex; align-items: center; }
    #btn-feedback:hover { background: rgba(52,211,153,0.22); border-color: rgba(52,211,153,0.6); }

    #graph-container {
      position: fixed; top: 60px; left: 0; right: 0; bottom: 0; z-index: 2; overflow: hidden;
      transition: padding-right 0.25s ease;
    }
    svg#graph {
      width: 100%; height: 100%; display: block; background: #030a1a;
    }

    .node-card {
      cursor: pointer; user-select: none; transition: all 0.15s ease;
      filter: drop-shadow(0 0 8px rgba(0,0,0,0.3));
    }
    .node-card:hover { filter: drop-shadow(0 0 16px rgba(0,0,0,0.5)); }
    .node-card.selected { filter: drop-shadow(0 0 24px rgba(255,255,255,0.4)); }
    /* Invite pulse on meta-cluster nodes until user first clicks anything */
    body:not(.explored) .node-card[data-meta="true"] .node-rect {
      animation: domain-invite 2.5s ease-in-out infinite;
    }
    @keyframes domain-invite {
      0%,100% { stroke-width:2; fill-opacity:0.05; }
      50% { stroke-width:3.5; fill-opacity:0.18; }
    }
    .node-rect {
      stroke-width: 2; fill-opacity: 0.05; transition: all 0.15s ease;
    }
    .node-card:hover .node-rect { stroke-width: 2.5; fill-opacity: 0.1; }
    .node-card.selected .node-rect { stroke-width: 3; fill-opacity: 0.15; }
    .node-label { font-size: 12px; font-weight: 500; pointer-events: none; }
    .node-category { font-size: 10px; opacity: 0.7; pointer-events: none; }
    .expand-chip { font-size: 9px; pointer-events: auto; cursor: pointer; margin-top: 2px; background: rgba(255,255,255,0.15); border: 1px solid rgba(255,255,255,0.35); border-radius: 8px; padding: 1px 6px; color: rgba(255,255,255,0.9); letter-spacing: 0.2px; transition: background 0.15s; }
    .expand-chip:hover { background: rgba(255,255,255,0.28); border-color: rgba(255,255,255,0.6); }

    .link {
      stroke: rgba(255,255,255,0.15); stroke-width: 1.5; fill: none; marker-end: url(#arrowhead);
    }
    .link.xlink {
      stroke-dasharray: 4,3; stroke: rgba(200,200,200,0.2); marker-end: url(#arrowhead-x);
    }
    #arrowhead { fill: rgba(255,255,255,0.15); }
    #arrowhead-x { fill: rgba(200,200,200,0.2); }

    #legend {
      position: fixed; top: 70px; left: 20px; z-index: 25;
      background: rgba(4,12,28,0.95); border: 1px solid rgba(255,255,255,0.1);
      border-radius: 8px; padding: 12px; min-width: 160px; max-height: calc(100vh - 120px); overflow-y: auto;
    }
    .legend-title { font-size: 12px; font-weight: 600; margin-bottom: 8px; color: #a78bfa; }
    .legend-item {
      display: flex; align-items: center; gap: 8px; padding: 6px; cursor: pointer;
      border-radius: 4px; transition: background 0.2s;
    }
    .legend-item:hover { background: rgba(255,255,255,0.08); }
    .legend-item.active { background: rgba(167,139,250,0.2); border-left: 2px solid #a78bfa; padding-left: 4px; }
    .legend-dot { width: 10px; height: 10px; border-radius: 50%; flex-shrink: 0; }
    .legend-cluster { font-size: 11px; font-weight: 600; padding: 5px 6px; cursor: pointer; border-radius: 4px; display: flex; align-items: center; gap: 6px; transition: background 0.15s; }
    .legend-cluster:hover { background: rgba(255,255,255,0.08); }
    .legend-cluster-arrow { font-size: 9px; color: rgba(255,255,255,0.4); transition: transform 0.2s; }
    .legend-cluster-arrow.open { transform: rotate(90deg); }
    .legend-domains { padding-left: 16px; overflow: hidden; }
    .legend-domains.collapsed { display: none; }

    #panel {
      position: fixed; right: 0; top: 0; width: 520px; min-width: 360px; max-width: 85vw; height: 100%;
      background: #07111f; border-left: 1px solid rgba(255,255,255,0.08);
      z-index: 30; overflow-y: auto; padding: 28px 24px 40px;
      transform: translateX(100%); transition: transform 0.25s ease;
    }
    #panel.open { transform: translateX(0); }
    #panel.resizing { transition: none; }
    #panel-resize {
      position: absolute; left: -4px; top: 0; width: 12px; height: 100%;
      cursor: col-resize; z-index: 31;
      background: transparent;
      transition: background 0.15s;
    }
    #panel-resize::after {
      content: ''; position: absolute; left: 5px; top: 0; width: 2px; height: 100%;
      background: transparent; transition: background 0.15s;
    }
    #panel-resize:hover::after, #panel-resize.dragging::after { background: rgba(56,189,248,0.5); }
    #panel-resize:hover, #panel-resize.dragging { background: rgba(56,189,248,0.08); }
    #panel-close {
      position: absolute; top: 16px; right: 16px;
      background: transparent; border: none; color: rgba(255,255,255,0.4);
      font-size: 18px; cursor: pointer; padding: 4px;
    }
    #panel-close:hover { color: #e2e8f0; }
    #panel-focus {
      position: absolute; top: 16px; right: 48px;
      background: transparent; border: none; color: rgba(255,255,255,0.4);
      font-size: 15px; cursor: pointer; padding: 4px; line-height: 1;
      transition: color 0.15s;
    }
    #panel-focus:hover { color: #a78bfa; }
    #panel-share {
      position: absolute; top: 16px; right: 80px;
      background: transparent; border: none; color: rgba(255,255,255,0.4);
      font-size: 15px; cursor: pointer; padding: 4px;
      transition: color 0.15s;
    }
    #panel-share:hover { color: #34d399; }
    .share-toast {
      position: fixed; bottom: 28px; left: 50%; transform: translateX(-50%);
      background: #0f172a; color: #34d399;
      border: 1px solid rgba(52,211,153,0.3);
      padding: 8px 20px; border-radius: 8px;
      font-size: 13px; font-weight: 600;
      pointer-events: none; opacity: 0;
      transition: opacity 0.2s; z-index: 9999;
    }
    .share-toast.visible { opacity: 1; }
    /* Focus / reading mode */
    body.focus-mode #graph-container { display: none; }
    body.focus-mode #legend { display: none; }
    body.focus-mode #kb-hints { display: none; }
    body.focus-mode #panel {
      width: 100vw !important; max-width: 900px;
      left: 50%; transform: translateX(-50%);
      border-left: none; border-radius: 0;
      padding: 40px 60px;
    }
    body.focus-mode #panel.open { transform: translateX(-50%); }
    body.focus-mode #panel-focus { color: #a78bfa; }
    body.focus-mode #panel-resize { display: none; }

    #panel-depth-label {
      font-size: 11px; font-weight: 700; letter-spacing: 0.12em;
      color: #34d399; text-transform: uppercase; margin-bottom: 10px;
    }
    .panel-cat-badge {
      display: inline-block; padding: 3px 9px; border-radius: 4px;
      font-size: 11px; font-weight: 600; margin-bottom: 10px; border: 1px solid;
    }
    .panel-title { font-size: 28px; font-weight: 700; margin-bottom: 14px; color: #f1f5f9; line-height: 1.2; }
    .panel-desc { font-size: 14px; line-height: 1.6; margin-bottom: 14px; color: #94a3b8; }
    #ps-deepdive {
      display: inline-flex; align-items: center; gap: 6px;
      margin-bottom: 20px;
      padding: 7px 14px; border-radius: 8px;
      background: rgba(99,102,241,0.15); border: 1px solid rgba(99,102,241,0.35);
      color: #a5b4fc; font-size: 13px; font-weight: 600;
      text-decoration: none; transition: background 0.15s, color 0.15s;
    }
    #ps-deepdive:hover { background: rgba(99,102,241,0.28); color: #c7d2fe; }

    .panel-section {
      margin-bottom: 22px; padding-bottom: 20px; border-bottom: 1px solid rgba(255,255,255,0.06);
    }
    .panel-section:last-child { border-bottom: none; }
    .panel-section-title {
      font-size: 13px; font-weight: 700; color: #e2e8f0; margin-bottom: 12px;
      display: flex; justify-content: space-between; align-items: center;
    }
    .copy-btn {
      background: rgba(52,211,153,0.15); border: 1px solid rgba(52,211,153,0.35);
      color: #34d399; padding: 4px 12px; border-radius: 6px; font-size: 12px;
      font-weight: 600; cursor: pointer; transition: background 0.2s;
    }
    .copy-btn:hover { background: rgba(52,211,153,0.28); }
    .ref-link {
      display: block; color: #93c5fd; font-size: 13px; text-decoration: none;
      padding: 6px 0; border-bottom: 1px solid rgba(255,255,255,0.06);
      transition: color 0.2s;
    }
    .ref-link:last-child { border-bottom: none; }
    .ref-link:hover { color: #bfdbfe; }

    /* ORDERED LEARNING PATH */
    .learn-path-ordered {
      display: flex; flex-wrap: wrap; align-items: center;
      gap: 6px; padding: 4px 0 8px;
    }
    .learn-path-ordered .ref-link {
      display: inline-block; border-bottom: none; padding: 5px 10px;
      background: rgba(99,102,241,0.12); border: 1px solid rgba(99,102,241,0.3);
      border-radius: 20px; font-size: 12px; white-space: nowrap;
    }
    .learn-path-ordered .ref-link:hover { background: rgba(99,102,241,0.25); color: #bfdbfe; }
    .learn-path-arrow {
      color: #6366f1; font-size: 14px; font-weight: 600; flex-shrink: 0;
    }
    .learn-divider {
      border: none; border-top: 1px solid rgba(255,255,255,0.08);
      margin: 8px 0;
    }

    /* KEY QUESTIONS */
    .qs-group { margin-bottom: 14px; }
    .qs-group:last-child { margin-bottom: 0; }
    .qs-role {
      font-size: 0.68rem; font-weight: 700; text-transform: uppercase;
      letter-spacing: 0.07em; color: #34d399; margin-bottom: 5px;
    }
    .qs-list { margin: 0; padding-left: 14px; }
    .qs-list li {
      font-size: 0.82rem; color: #94a3b8; margin-bottom: 5px;
      line-height: 1.45;
    }
    .qs-list li:last-child { margin-bottom: 0; }

    .code-block {
      background: rgba(0,0,0,0.4); border: 1px solid rgba(255,255,255,0.08);
      border-radius: 6px; padding: 14px; font-family: 'Monaco', 'Menlo', monospace;
      font-size: 12px; line-height: 1.5; overflow-x: auto; color: #cbd5e1;
      user-select: none; -webkit-user-select: none; cursor: default;
    }
    .diag-block {
      background: rgba(56,189,248,0.04); border: 1px solid rgba(56,189,248,0.18);
      border-radius: 8px; padding: 16px; font-family: 'Monaco', 'Menlo', monospace;
      font-size: 11.5px; line-height: 1.7; overflow-x: auto; color: #7dd3fc;
      white-space: pre;
    }

    .panel-section p { font-size: 14px; line-height: 1.6; color: #94a3b8; }

    .panel-pills { display: flex; flex-wrap: wrap; gap: 8px; }
    .panel-pill {
      display: inline-flex; align-items: center; gap: 4px;
      background: rgba(255,255,255,0.06); border: 1px solid rgba(255,255,255,0.12);
      padding: 7px 14px; border-radius: 20px; font-size: 13px; cursor: pointer;
      transition: all 0.15s; color: #cbd5e1; white-space: nowrap;
    }
    .panel-pill:hover {
      background: rgba(255,255,255,0.1); border-color: rgba(255,255,255,0.22);
      color: #f1f5f9;
    }
    .panel-pill.pill-tool {
      background: rgba(52,211,153,0.07); border-color: rgba(52,211,153,0.2);
      color: #a7f3d0;
    }
    .panel-pill.pill-tool:hover {
      background: rgba(52,211,153,0.12); border-color: rgba(52,211,153,0.35);
    }
    /* SUB-TOPIC PILLS */
    #ps-subtopics-list { display: flex; flex-wrap: wrap; gap: 8px; }
    .subtopic-pill {
      background: rgba(99,102,241,0.1); border-color: rgba(99,102,241,0.28);
      color: #a5b4fc;
    }
    .subtopic-pill:hover {
      background: rgba(99,102,241,0.2); border-color: rgba(99,102,241,0.5);
      color: #c7d2fe;
    }

    #panel-breadcrumb {
      display: flex; align-items: center; flex-wrap: wrap; gap: 4px;
      margin-bottom: 12px; font-size: 12px;
    }
    .bc-item {
      color: #38bdf8; cursor: pointer; transition: color 0.15s;
      text-decoration: underline; text-decoration-color: rgba(56,189,248,0.35);
      text-underline-offset: 2px;
    }
    .bc-item:hover { color: #7dd3fc; text-decoration-color: rgba(125,211,252,0.6); }
    .bc-item.bc-current { color: #64748b; cursor: default; text-decoration: none; }
    .bc-sep { color: #334155; font-size: 10px; }

    #panel-back {
      display: none; align-items: center; gap: 6px;
      background: rgba(56,189,248,0.08); border: 1px solid rgba(56,189,248,0.2);
      color: #38bdf8; padding: 7px 14px; border-radius: 8px;
      font-size: 13px; cursor: pointer; transition: all 0.15s;
      margin-bottom: 18px; width: fit-content;
    }
    #panel-back:hover { background: rgba(56,189,248,0.14); border-color: rgba(56,189,248,0.35); }
    #panel-back.visible { display: flex; }

    .path-item {
      display: flex; align-items: flex-start; gap: 12px;
      padding: 12px 14px; border-radius: 10px;
      background: rgba(255,255,255,0.03); border: 1px solid rgba(255,255,255,0.07);
      cursor: pointer; transition: all 0.15s; margin-bottom: 8px;
    }
    .path-item:last-child { margin-bottom: 0; }
    .path-item:hover { background: rgba(255,255,255,0.07); border-color: rgba(255,255,255,0.14); }
    .path-num {
      min-width: 22px; height: 22px; border-radius: 50%;
      background: rgba(52,211,153,0.12); color: #34d399;
      display: flex; align-items: center; justify-content: center;
      font-size: 11px; font-weight: 700; flex-shrink: 0; margin-top: 1px;
    }
    .path-node-name { font-size: 14px; font-weight: 600; color: #e2e8f0; margin-bottom: 3px; }
    .path-note { font-size: 12px; color: #475569; line-height: 1.4; }

    #kb-hints {
      position: fixed; bottom: 20px; left: 20px; z-index: 25;
      background: rgba(4,12,28,0.95); border: 1px solid rgba(255,255,255,0.1);
      border-radius: 8px; padding: 12px; font-size: 11px; max-width: 200px;
    }
    .kb-hint { margin: 4px 0; color: #a78bfa; }
    .kb-hint strong { color: #34d399; }

    /* ── Welcome overlay ── */
    #welcome-overlay {
      position: fixed; inset: 0; z-index: 200;
      background: rgba(3,10,26,0.88); backdrop-filter: blur(6px);
      display: flex; align-items: center; justify-content: center;
      transition: opacity 0.4s;
    }
    #welcome-overlay.hidden { opacity:0; pointer-events:none; display:none; }
    #welcome-card {
      background: #07111f; border: 1px solid rgba(56,189,248,0.25);
      border-radius: 16px; padding: 40px 44px 36px;
      max-width: 560px; width: 90%; text-align: center;
      box-shadow: 0 24px 80px rgba(0,0,0,0.6);
    }
    #welcome-logo { font-size: 36px; margin-bottom: 10px; }
    #welcome-title { font-size: 24px; font-weight: 700; color: #f1f5f9; margin-bottom: 6px; }
    #welcome-sub { font-size: 14px; color: #64748b; margin-bottom: 32px; }
    #welcome-steps { display: flex; gap: 16px; margin-bottom: 32px; }
    .ws {
      flex: 1; background: rgba(56,189,248,0.05);
      border: 1px solid rgba(56,189,248,0.14);
      border-radius: 12px; padding: 18px 12px;
    }
    .ws-icon { font-size: 22px; margin-bottom: 8px; }
    .ws-head { font-size: 13px; font-weight: 600; color: #e2e8f0; margin-bottom: 6px; }
    .ws-body { font-size: 12px; color: #64748b; line-height: 1.5; }
    #welcome-start {
      background: linear-gradient(135deg,#38bdf8,#6366f1);
      border: none; border-radius: 10px; color: #fff;
      font-size: 15px; font-weight: 600; padding: 13px 36px;
      cursor: pointer; transition: opacity 0.2s; width: 100%; margin-bottom: 14px;
    }
    #welcome-start:hover { opacity: 0.88; }
    #welcome-footnote { font-size: 12px; color: #334155; }

    .search-highlight { animation: pulse-glow 0.6s ease-in-out; }
    @keyframes pulse-glow {
      0%, 100% { filter: drop-shadow(0 0 8px rgba(52,211,153,0.6)); }
      50% { filter: drop-shadow(0 0 16px rgba(52,211,153,1)); }
    }
    /* Search state */
    .node-card.search-fade { opacity: 0.1; pointer-events: none; transition: opacity 0.15s; }
    .node-card.search-match { opacity: 1; transition: opacity 0.15s; }
    .node-card.search-match .node-rect { filter: drop-shadow(0 0 8px rgba(52,211,153,0.85)); }
    #topbar-search { transition: border-color 0.2s, background 0.2s; }
    #topbar-search.no-results { border-color: rgba(239,68,68,0.7) !important; background: rgba(239,68,68,0.08) !important; }
    #topbar-search:focus { outline: none; border-color: rgba(255,255,255,0.3); }
    #search-count { font-size: 11px; color: rgba(255,255,255,0.45); margin-left: 4px; white-space: nowrap; align-self: center; }
    /* ◆ indicator on nodes that have code / diagrams / tips */
    .rich-dot { font-size: 7px; color: rgba(56,189,248,0.85); pointer-events: none; animation: rich-pulse 2.8s ease-in-out infinite; }
    @keyframes rich-pulse { 0%,100%{opacity:0.4} 50%{opacity:1} }
    /* Context menu (right-click) */
    #ctx-menu {
      position: fixed; z-index: 1000; display: none;
      background: rgba(10,18,38,0.98); border: 1px solid rgba(255,255,255,0.12);
      border-radius: 8px; padding: 4px; min-width: 170px;
      box-shadow: 0 8px 24px rgba(0,0,0,0.5);
    }
    #ctx-menu.visible { display: block; }
    .ctx-item {
      padding: 8px 12px; font-size: 12px; color: #cbd5e1; cursor: pointer;
      border-radius: 5px; display: flex; align-items: center; gap: 8px;
      transition: background 0.15s;
    }
    .ctx-item:hover { background: rgba(167,139,250,0.15); color: #e2e8f0; }
    .ctx-item .ctx-icon { font-size: 13px; width: 16px; text-align: center; }
    .ctx-sep { height: 1px; background: rgba(255,255,255,0.07); margin: 3px 0; }
    /* Bottom onboarding hint bar */
    #hint-bar {
      position: fixed; bottom: 0; left: 0; right: 0; z-index: 50;
      background: rgba(4,12,28,0.95); border-top: 1px solid rgba(56,189,248,0.22);
      padding: 11px 24px; display: flex; align-items: center; justify-content: center;
      gap: 20px; font-size: 13px; color: #94a3b8; backdrop-filter: blur(10px);
      transition: opacity 0.5s, transform 0.5s;
    }
    #hint-bar.hidden { opacity: 0; pointer-events: none; transform: translateY(100%); }
    #hint-bar strong { color: #38bdf8; }
    .hint-sep { color: #334155; margin: 0 4px; }
    #hint-close {
      background: none; border: 1px solid rgba(255,255,255,0.12); border-radius: 5px;
      color: #64748b; cursor: pointer; font-size: 12px; padding: 3px 10px;
      transition: all 0.15s; white-space: nowrap;
    }
    #hint-close:hover { color: #94a3b8; border-color: rgba(255,255,255,0.25); }

    ::-webkit-scrollbar { width: 8px; }
    ::-webkit-scrollbar-track { background: transparent; }
    ::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.15); border-radius: 4px; }
    ::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.25); }

    /* Drag handle — hidden on desktop, shown on mobile */
    #panel-drag-handle { display: none; }

    /* ── MOBILE ────────────────────────────────────────────── */
    @media (max-width: 768px) {

      /* Topbar — hide view buttons, compact layout */
      .topbar-btn-group { display: none; }
      #topbar-right { display: none; }
      #topbar-title { min-width: unset; font-size: 15px; }
      #topbar-search { max-width: unset; flex: 1; }
      #topbar { gap: 10px; padding: 0 12px; }
      #search-count { display: none; }

      /* Legend + KB hints — hidden on mobile */
      #legend { display: none; }
      #kb-hints { display: none; }

      /* Panel — bottom sheet */
      #panel {
        width: 100% !important;
        min-width: unset !important;
        max-width: 100% !important;
        height: 72vh;
        top: auto;
        bottom: 0;
        right: 0;
        left: 0;
        border-left: none;
        border-top: 1px solid rgba(255,255,255,0.12);
        border-radius: 16px 16px 0 0;
        transform: translateY(100%);
        transition: transform 0.3s cubic-bezier(0.32, 0.72, 0, 1);
        padding: 16px 20px 40px;
      }
      #panel.open { transform: translateY(0); }

      /* Drag handle at top of panel — visible on mobile */
      #panel-drag-handle {
        display: block;
        width: 36px; height: 4px;
        background: rgba(255,255,255,0.2);
        border-radius: 2px;
        margin: 0 auto 16px;
        cursor: grab;
        flex-shrink: 0;
      }

      /* Hide desktop-only panel controls */
      #panel-resize { display: none; }
      #panel-focus { display: none; }

      /* Reposition close + share on mobile */
      #panel-close { top: 12px; right: 12px; }
      #panel-share { top: 12px; right: 44px; }

      /* Focus mode on mobile — still bottom sheet */
      body.focus-mode #panel {
        width: 100% !important;
        max-width: 100% !important;
        left: 0;
        transform: translateY(0) !important;
        border-radius: 16px 16px 0 0;
      }

      /* Graph always full screen on mobile — panel overlays */
      #graph-container { padding-right: 0 !important; }

      /* Welcome card — stack steps vertically */
      #welcome-card { padding: 24px 18px 20px; }
      #welcome-steps { flex-direction: column; gap: 8px; }
      #welcome-title { font-size: 20px; }

      /* Hint bar — simpler */
      #hint-bar { font-size: 12px; padding: 10px 16px; gap: 10px; flex-wrap: wrap; justify-content: flex-start; }

      /* Panel content — smaller type */
      .panel-title { font-size: 22px; }
      .panel-desc { font-size: 13px; }

      /* Bigger tap targets */
      .panel-pill { padding: 10px 14px; }
      .path-item { padding: 14px; }
      .ref-link { padding: 10px 0; }
    }

/* ── Related Concepts widget ──────────────────────────────────────────────── */
.related-concepts {
  margin: 2.5rem 0 1.5rem;
  padding: 1.5rem 1.75rem;
  background: var(--bg-card, #1a1f2e);
  border: 1px solid rgba(255,255,255,0.07);
  border-radius: 12px;
}

.rc-heading {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted, #8899aa);
  margin: 0 0 1rem;
}

.rc-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.rc-card {
  display: inline-flex;
  align-items: center;
  padding: 0.4rem 0.85rem;
  border-radius: 6px;
  background: rgba(255,255,255,0.04);
  border: 1px solid color-mix(in srgb, var(--rc-accent, #64748b) 35%, transparent);
  color: var(--text-primary, #e2e8f0);
  text-decoration: none;
  font-size: 0.85rem;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
}

.rc-card:hover {
  background: color-mix(in srgb, var(--rc-accent, #64748b) 15%, transparent);
  border-color: var(--rc-accent, #64748b);
  transform: translateY(-1px);
  color: #fff;
}

.rc-label {
  white-space: nowrap;
}

@media (max-width: 600px) {
  .related-concepts { padding: 1.1rem 1rem; }
  .rc-card { font-size: 0.8rem; padding: 0.35rem 0.7rem; }
}

/* ── Contextual inline concept links ─────────────────────────────────────── */
.concept-link {
  color: var(--accent, #63b3ed);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent, #63b3ed) 40%, transparent);
  text-underline-offset: 2px;
  transition: color 0.15s, text-decoration-color 0.15s;
}

.concept-link:hover {
  color: #fff;
  text-decoration-color: var(--accent, #63b3ed);
}