:root {
    --bg: #0b0f14;
    --panel: #121823;
    --panel2: #0f1520;
    --text: #e9eef7;
    --muted: #9aa7bd;
    --border: rgba(255,255,255,0.08);
    --ok: #2bd576;
    --fail: #ff5c5c;
    --btn: #1f2a3a;
  }
  * { box-sizing: border-box; }
  body {
    margin: 0;
    font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
    background: radial-gradient(1200px 800px at 20% 0%, #152034 0%, var(--bg) 60%);
    color: var(--text);
  }
  header {
    padding: 28px 20px 10px;
    max-width: 1100px;
    margin: 0 auto;
  }
  .header-row {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
  }
  .header-meta {
    color: var(--muted);
    font-size: 12px;
    padding-top: 4px;
  }
  h1 {
    margin: 0 0 6px;
    font-size: 20px;
    letter-spacing: 0.2px;
    font-weight: 500;
    color: rgba(233,238,247,0.90);
  }
  .site-title {
    font-size: 20px;
    font-weight: 500;
    color: rgba(233,238,247,0.90);
  }
  .site-title-link {
    color: inherit;
    text-decoration: none;
  }
  .site-title-link:hover {
    text-decoration: underline;
    color: rgba(245,248,255,0.98);
  }
  .home-hint {
    font-size: 11px;
    color: rgba(154,167,189,0.9);
    letter-spacing: 0.04em;
    margin-left: 6px;
  }
  .sub {
    margin: 0;
    color: var(--muted);
    font-size: 13px;
  }
  .sub.sub-empty {
    display: none;
  }
  .wrap {
    max-width: 1100px;
    margin: 0 auto;
    padding: 16px 20px 40px;
  }
  .topnav {
    margin-top: 12px;
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
  }
  .topnav.is-hidden {
    display: none;
  }
  .header-meta.is-hidden {
    display: none;
  }
  .nav-link {
    display: inline-block;
    padding: 6px 10px;
    border-radius: 999px;
    border: 1px solid var(--border);
    color: var(--muted);
    text-decoration: none;
    font-size: 12px;
    background: rgba(18,24,35,0.45);
  }
  .nav-link.is-active {
    color: var(--text);
    border-color: rgba(124,156,255,0.35);
    background: rgba(31,42,58,0.60);
  }
  .layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
  }
  .toolbar {
    display: flex;
    gap: 10px;
    align-items: center;
    justify-content: space-between;
    padding: 12px 14px;
    background: rgba(18,24,35,0.65);
    border: 1px solid var(--border);
    border-radius: 12px;
    backdrop-filter: blur(10px);
    margin-bottom: 14px;
  }
  .search {
    width: 380px;
    max-width: 100%;
    padding: 10px 12px;
    border-radius: 10px;
    border: 1px solid var(--border);
    background: var(--panel2);
    color: var(--text);
    outline: none;
  }
  .grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
  }
  .card {
    background: rgba(18,24,35,0.75);
    border: 1px solid var(--border);
    border-radius: 14px;
    overflow: hidden;
  }
  .card-top {
    display: flex;
    align-items: start;
    justify-content: space-between;
    gap: 12px;
    padding: 14px 14px 10px;
    border-bottom: 1px solid var(--border);
  }
  h2 {
    margin: 0;
    font-size: 16px;
  }
  .meta {
    margin-top: 6px;
    display: flex;
    gap: 8px;
    align-items: center;
    color: var(--muted);
    font-size: 12px;
  }
  .meta-path { font-size: 10px; }
  .mono { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace; }
  .pill {
    padding: 2px 8px;
    border-radius: 999px;
    font-size: 11px;
    border: 1px solid var(--border);
  }
  .pill.ok { color: var(--ok); border-color: rgba(43,213,118,0.35); }
  .pill.fail { color: var(--fail); border-color: rgba(255,92,92,0.35); }
  .pill.warn { color: #f5c451; border-color: rgba(245,196,81,0.35); }
  .pill.info { color: #6db1ff; border-color: rgba(109,177,255,0.35); }
  .pill.fab-pill {
    color: #ffd28a;
    border-color: rgba(255,210,138,0.35);
  }
  .actions { display: flex; gap: 8px; }
  .variant-select {
    appearance: none;
    padding: 8px 10px;
    border-radius: 10px;
    border: 1px solid var(--border);
    background: var(--btn);
    color: var(--text);
    font-size: 12px;
    cursor: pointer;
  }
  .variant-select:hover { filter: brightness(1.08); }
  .variant-select:focus {
    outline: 2px solid rgba(124,156,255,0.35);
    outline-offset: 2px;
  }
  .btn {
    display: inline-block;
    padding: 8px 10px;
    border-radius: 10px;
    background: var(--btn);
    border: 1px solid var(--border);
    color: var(--text);
    text-decoration: none;
    font-size: 12px;
  }
  .btn:hover { filter: brightness(1.08); }
  .btn-disabled { opacity: 0.5; }
  .card-body {
    display: grid;
    grid-template-columns: clamp(300px, 45%, 460px) 1fr;
    gap: 4px;
    padding: 12px 14px 14px;
  }

  .info-col {
    display: flex;
    flex-direction: column;
    min-width: 0;
    height: 100%;
  }
  
  @media (max-width: 900px) {
    .card-body { grid-template-columns: 1fr; }
    .layout{ grid-template-columns: 1fr; }
  }

  .preview {
    background: rgba(15,21,32,0.7);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 10px;
    min-height: 220px;
    aspect-ratio: 4 / 5;
    max-height: clamp(260px, 45vh, 520px);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
  }
  .thumb {
    width: 50%;
    height: auto;
    display: block;
    margin: 0 auto;
    border-radius: 8px;
    max-height: 100%;
    object-fit: contain;
  }
  .thumb-missing {
    width: 100%;
    border-radius: 8px;
    color: var(--muted);
    text-align: center;
    padding: 30px 10px;
  }
  .info h3 {
    margin: 0;
    font-size: 13px;
    color: var(--muted);
    letter-spacing: 0.2px;
  }

  .info-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 8px;
  }

  /* Tabs */
  .tabs {
    display: inline-flex;
    gap: 6px;
    padding: 4px;
    border-radius: 12px;
    background: rgba(15,21,32,0.40);
    border: 1px solid var(--border);
    flex-wrap: wrap;
    justify-content: flex-end;
  }

  .tab-btn {
    appearance: none;
    border: 1px solid transparent;
    background: transparent;
    color: var(--muted);
    font-size: 12px;
    padding: 6px 10px;
    border-radius: 10px;
    cursor: pointer;
    user-select: none;
  }

  .tab-btn:hover { filter: brightness(1.10); }

  .tab-btn.is-active {
    color: var(--text);
    background: rgba(31,42,58,0.75);
    border-color: rgba(255,255,255,0.10);
  }

  /* Panels */
  .tab-panel {
    margin-top: 10px;
  }

  /* Doc panels readability: constrain measure */
  .doc-wrap {
    max-width: 820px;
  }

  .doc.md {
    font-size: 13px;
    line-height: 1.65;
  }
  .doc.md * {
    line-height: inherit;
  }

  .doc {
    padding: 10px 12px;
    border-radius: 12px;
    background: rgba(15,21,32,0.45);
    border: 1px solid var(--border);
  }

  /* markdown-ish styling */
  .md-h {
    padding-top: 6px;
    border-top: 1px solid rgba(255,255,255,0.08);
    margin: 14px 0 10px;
    font-size: 14px;
    font-weight: 750;
    letter-spacing: 0.02em;
    color: var(--text);
  }
  .md-h:first-child {
    border-top: none;
    padding-top: 0;
  }
  .md-p {
    margin: 0 0 12px;
    font-size: 13px;
    line-height: 1.68;
    color: rgba(233,238,247,0.92);
  }

  .md-ul {
    margin: 6px 0 12px 22px;
    padding-left: 0;
    font-size: 13px;
    line-height: 1.65;
    list-style-position: outside;
  }
  .md-ul li {
    margin: 8px 0;
    padding-left: 2px;
    color: rgba(233,238,247,0.90);
  }
  .md-ul li br {
    display: block;
    content: "";
    margin-top: 3px;
  }

  /* Code blocks comfort */
  .md-code {
    margin: 0 0 12px;
    padding: 12px 14px;
    border-radius: 10px;
    border: 1px solid rgba(255,255,255,0.12);
    background: rgba(0,0,0,0.30);
    overflow: auto;
  }
  .md-code code {
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
    font-size: 12px;
    line-height: 1.50;
    color: var(--text);
  }
  .md-inline {
    padding: 1px 6px;
    border-radius: 8px;
    border: 1px solid rgba(255,255,255,0.10);
    background: rgba(0,0,0,0.22);
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
    font-size: 12px;
  }

  /* Field list (Params/Ports) readability + row separators */
  .md-dl {
    margin: 0 0 12px;
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 6px 14px;
    align-items: start;
    position: relative;
  }
  @media (max-width: 700px) {
    .md-dl { grid-template-columns: 1fr; }
  }
  .md-dt {
    padding-top: 8px;
    margin: 0;
    color: rgba(233,238,247,0.98);
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    font-size: 12px;
    font-weight: 700;
  }
  .md-type {
    color: rgba(154,167,189,0.95);
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    font-size: 11px;
    font-weight: 600;
  }
  .md-dd {
    padding-top: 8px;
    margin: 0;
    margin-bottom: 10px;
    color: rgba(233,238,247,0.90);
    line-height: 1.55;
    font-size: 13px;
    border-top: 1px dashed rgba(255,255,255,0.06);
  }

  .kvlist {
    background: rgba(15,21,32,0.55);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 10px;
  }
  .card-foot {
    margin-top: auto;
    display: flex;
    gap: 8px;
    align-items: center;
    justify-content: flex-end;
    opacity: 0.70;
  }
  .kv {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 10px;
    padding: 6px 0;
    border-bottom: 1px dashed rgba(255,255,255,0.08);
    font-size: 12px;
  }
  .kv:last-child { border-bottom: none; }
  .k {
    color: var(--muted);
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  }
  .v { color: var(--text); word-break: break-word; }
  .muted { color: var(--muted); font-size: 12px; }
  .error {
    margin: 0;
    white-space: pre-wrap;
    color: var(--fail);
    font-size: 12px;
  }
  footer {
    max-width: 1100px;
    margin: 0 auto;
    padding: 16px 20px 28px;
    color: var(--muted);
    font-size: 12px;
    display: grid;
    gap: 6px;
  }

  /* Overview + simple pages */
  .overview-hero {
    padding: 18px 18px 20px;
    background:
      radial-gradient(700px 220px at 10% 0%, rgba(124,156,255,0.16), transparent 60%),
      linear-gradient(180deg, rgba(18,24,35,0.70), rgba(12,16,24,0.85));
    border: 1px solid rgba(255,255,255,0.10);
    border-radius: 16px;
    margin-bottom: 16px;
    box-shadow: 0 18px 40px rgba(0,0,0,0.35);
  }
  .overview-hero.is-hidden {
    display: none;
  }
  .overview-hero .overview-grid {
    margin-top: 14px;
  }
  .pdk-group {
    margin-top: 18px;
    padding-top: 14px;
    border-top: 1px solid rgba(255,255,255,0.08);
  }
  .pdk-group-head {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 10px;
  }
  .pdk-group-title {
    font-size: 13px;
    font-weight: 750;
    color: rgba(233,238,247,0.95);
  }
  .pdk-group-sub {
    font-size: 12px;
    color: rgba(154,167,189,0.9);
  }
  .hero-top {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
    flex-wrap: wrap;
  }
  .hero-eyebrow {
    font-size: 11px;
    letter-spacing: 0.28em;
    color: rgba(154,167,189,0.85);
    text-transform: uppercase;
    margin-bottom: 6px;
  }
  .hero-title {
    font-size: 22px;
    font-weight: 850;
    color: rgba(245,248,255,0.98);
    margin-bottom: 8px;
  }
  .hero-sub {
    color: rgba(154,167,189,0.90);
    font-size: 12.5px;
  }
  .hero-legal {
    margin-top: 8px;
    color: rgba(154,167,189,0.85);
    font-size: 11px;
    letter-spacing: 0.02em;
  }
  .hero-badges {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: 2px;
  }
  .hero-badges .badge {
    padding: 6px 10px;
    border-radius: 999px;
    border: 1px solid rgba(124,156,255,0.18);
    background: rgba(15,21,32,0.45);
    font-size: 10.5px;
    color: rgba(233,238,247,0.75);
  }
  .hero-badges .badge strong {
    color: rgba(233,238,247,0.92);
    font-weight: 700;
    margin-left: 4px;
  }
  .overview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
    gap: 14px;
  }
  .overview-card {
    display: block;
    padding: 18px;
    border-radius: 14px;
    border: 1px solid rgba(255,255,255,0.10);
    background:
      linear-gradient(180deg, rgba(16,22,33,0.75), rgba(12,16,24,0.85));
    text-decoration: none;
    color: var(--text);
    position: relative;
    overflow: hidden;
  }
  .overview-card::after {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(240px 120px at 10% 0%, rgba(124,156,255,0.14), transparent 60%);
    opacity: 0.8;
    pointer-events: none;
  }
  .overview-card:hover { filter: brightness(1.08); }
  .overview-card .card-title {
    font-size: 14px;
    font-weight: 750;
    margin-bottom: 6px;
    position: relative;
    z-index: 1;
  }
  .overview-card .card-sub {
    color: rgba(170,182,200,0.92);
    font-size: 12px;
    line-height: 1.5;
    position: relative;
    z-index: 1;
  }
  .overview-card .card-meta {
    margin-top: 10px;
    font-size: 11px;
    color: rgba(154,167,189,0.9);
    position: relative;
    z-index: 1;
  }

  .overview-demo {
    margin-top: 14px;
    border: 1px solid rgba(255,255,255,0.10);
    border-radius: 14px;
    padding: 12px;
    background: linear-gradient(180deg, rgba(15,21,32,0.55), rgba(12,16,24,0.78));
  }
  .overview-demo-title {
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: rgba(233,238,247,0.9);
    margin-bottom: 10px;
  }
  .overview-demo-gif {
    display: block;
    width: 50%;
    height: auto;
    margin: 0 auto;
    border-radius: 10px;
    border: 1px solid rgba(255,255,255,0.12);
    background: rgba(8,12,18,0.55);
  }

  .page-panel {
    padding: 16px;
    background: rgba(18,24,35,0.65);
    border: 1px solid var(--border);
    border-radius: 14px;
  }
  .page-panel h2 {
    margin-top: 0;
    font-size: 16px;
  }
  .page-head {
    margin-bottom: 10px;
    padding: 10px 12px;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: rgba(15,21,32,0.45);
  }
  .page-head .sub {
    margin-top: 6px;
  }
  .layer-top {
    display: grid;
    grid-template-columns: 1.6fr 1fr;
    gap: 10px;
    margin-bottom: 10px;
  }
  .layer-top .page-head {
    margin-bottom: 0;
  }
  .layer-stats {
    margin-top: 0;
  }
  @media (max-width: 900px) {
    .layer-top {
      grid-template-columns: 1fr;
    }
  }
  .panel {
    margin-top: 10px;
    padding: 12px;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: rgba(15,21,32,0.55);
  }
  .panel-row {
    display: flex;
    justify-content: space-between;
    gap: 10px;
    padding: 6px 0;
    border-bottom: 1px dashed rgba(255,255,255,0.08);
    font-size: 12px;
  }
  .panel-row:last-child { border-bottom: none; }

  .layer-group {
    margin-top: 12px;
    border: 1px solid var(--border);
    border-radius: 12px;
    background: rgba(15,21,32,0.55);
    overflow: hidden;
  }
  .layer-group > summary {
    list-style: none;
    cursor: pointer;
    padding: 10px 12px;
    font-size: 13px;
    font-weight: 700;
    border-bottom: 1px solid rgba(255,255,255,0.06);
  }
  .layer-group > summary::-webkit-details-marker {
    display: none;
  }
  .layer-table-wrap {
    overflow: auto;
  }
  .layer-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 12px;
    table-layout: fixed;
  }
  .layer-table th,
  .layer-table td {
    padding: 8px 10px;
    border-bottom: 1px dashed rgba(255,255,255,0.08);
    text-align: left;
    vertical-align: middle;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
  .layer-table th {
    color: rgba(154,167,189,0.95);
    font-weight: 700;
    background: rgba(255,255,255,0.02);
  }
  .layer-table tr:last-child td {
    border-bottom: none;
  }
  .layer-color {
    display: inline-block;
    width: 14px;
    height: 14px;
    border-radius: 4px;
    border: 1px solid rgba(255,255,255,0.22);
  }
  .layer-table .col-ld { width: 80px; }
  .layer-table .col-purpose { width: 100px; }
  .layer-table .col-material { width: 120px; }
  .layer-table .col-color { width: 80px; }
  .layer-table .col-name { width: 160px; }
  .layer-table .col-thk { width: 120px; }
  .layer-table .col-zmin { width: 120px; }
  .layer-table .col-public { width: 80px; }

  .rules-summary { margin-bottom: 14px; }
  .rules-table td { white-space: normal; }
  .rules-table .rule-desc { color: rgba(233,238,247,0.82); }
  .rules-table .rule-layers { white-space: normal; }
  .rules-table .col-rule-id { width: 140px; }
  .rules-table .col-rule-summary { width: 190px; }
  .rules-table .col-rule-desc { width: 320px; }
  .rules-table .col-rule-layers { width: 220px; }
  .rules-table .col-rule-check { width: 170px; }
  .rules-table .col-rule-sev { width: 110px; }
  .rules-table .col-rule-waive { width: 90px; }

  .stack-viz-title {
    font-size: 13px;
    font-weight: 700;
    margin-bottom: 8px;
  }
  .stack-viz-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin-bottom: 12px;
  }
  .stack-canvas-title {
    font-size: 12px;
    color: rgba(154,167,189,0.95);
    margin-bottom: 6px;
  }
  .stack-canvas {
    border: 1px solid rgba(255,255,255,0.10);
    border-radius: 10px;
    background: rgba(0,0,0,0.18);
    padding: 8px;
  }
  .stack-scale {
    display: flex;
    justify-content: space-between;
    font-size: 11px;
    color: var(--muted);
    margin-bottom: 6px;
  }
  .stack-scale-vertical {
    display: flex;
    flex-direction: column;
    gap: 2px;
    font-size: 11px;
    color: var(--muted);
    margin-bottom: 6px;
  }
  .stack-bars {
    position: relative;
    height: 320px;
    --bridge-island-w: 7.5%;
    --bridge-island-half: calc(var(--bridge-island-w) / 2);
    --bridge-island-center-span: 50%;
    /* Extend bridge shell container beyond both bridge islands (outer-side overhang). */
    --bridge-strip-w: calc(var(--bridge-island-center-span) + var(--bridge-island-w));
    border-radius: 8px;
    border: 1px dashed rgba(255,255,255,0.14);
    background: linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.01));
    overflow: hidden;
  }
  .stack-bar {
    position: absolute;
    left: 0;
    border-radius: 4px;
    box-shadow: 0 0 0 1px rgba(255,255,255,0.14) inset;
    opacity: 0.95;
    transform: none;
  }
  .stack-bar--plane {
    left: 10px;
    right: 10px;
    width: auto;
    z-index: 1;
  }
  .stack-bar--strip {
    left: 12px;
    width: 33%;
    z-index: 2;
  }
  .stack-bar--strip-a {
    left: 12px;
  }
  .stack-bar--strip-b {
    right: 12px;
    left: auto;
  }
  .stack-bar--bridge-strip {
    left: calc(50% - (var(--bridge-strip-w) / 2));
    right: auto;
    width: var(--bridge-strip-w);
  }
  .stack-bar--bridge-strip-shell {
    background: transparent !important;
    border-radius: 0;
    opacity: 0.7;
    z-index: 2;
    box-shadow: none;
  }
  .bridge-dome-svg {
    display: block;
    width: 100%;
    height: 100%;
    filter: drop-shadow(0 1px 2px rgba(0,0,0,0.2));
  }
  .stack-bar--bridge-strip-core {
    z-index: 4;
  }
  .stack-bar--bridge-strip-dome {
    border-radius: 999px 999px 6px 6px;
    box-shadow:
      0 0 0 1px rgba(255,255,255,0.18) inset,
      0 2px 8px rgba(0,0,0,0.18);
  }
  .stack-bar--island {
    right: 12px;
    left: auto;
    width: 7.5%;
    z-index: 3;
  }
  .stack-bar--island-a {
    left: calc(50% - 9%);
    right: auto;
  }
  .stack-bar--island-b {
    left: calc(50% + 1.5%);
    right: auto;
  }
  .stack-bar--bridge-island-a {
    left: calc(25% - var(--bridge-island-half));
    right: auto;
    width: var(--bridge-island-w);
  }
  .stack-bar--bridge-island-b {
    left: calc(75% - var(--bridge-island-half));
    right: auto;
    width: var(--bridge-island-w);
  }
  .stack-legend {
    max-height: 260px;
    overflow: auto;
    border: 1px solid rgba(255,255,255,0.10);
    border-radius: 10px;
    padding: 8px 10px;
    background: rgba(0,0,0,0.16);
  }
  .stack-legend-row {
    display: grid;
    grid-template-columns: 16px 1fr;
    gap: 8px;
    align-items: center;
    padding: 5px 0;
    border-bottom: 1px dashed rgba(255,255,255,0.08);
  }
  .stack-legend-row .muted {
    grid-column: 2;
    font-size: 11px;
  }
  .stack-legend-row:last-child {
    border-bottom: none;
  }
  @media (max-width: 900px) {
    .stack-viz-layout {
      grid-template-columns: 1fr;
    }
  }

  /* section headers (collapsible) */
  .section {
    margin-top: 18px;
    padding: 10px 6px 6px;
    display: flex;
    align-items: center;
    gap: 12px;
    width: 100%;
    cursor: pointer;
    border: none;
    background: transparent;
    text-align: left;
    position: relative;
  }
  .section:focus {
    outline: 2px solid rgba(255,255,255,0.18);
    outline-offset: 4px;
    border-radius: 12px;
  }
  .section-title {
    position: relative;
    z-index: 1;
    font-size: 13px;
    color: var(--muted);
    letter-spacing: 0.12em;
    text-transform: uppercase;
    font-weight: 650;
    padding: 6px 10px;
    border: 1px solid var(--border);
    border-radius: 999px;
    background: rgba(18,26,40,0.65);
    box-shadow:
      0 0 8px rgba(160,190,255,0.28),
      inset 0 0 0 1px rgba(255,255,255,0.08);
    backdrop-filter: blur(6px);
  }
  .section::after {
    content: "";
    position: absolute;
    left: 6px;
    right: 6px;
    top: 50%;
    height: 2px;
    transform: translateY(-50%);
    background: linear-gradient(
      90deg,
      rgba(255,255,255,0.18),
      rgba(255,255,255,0.30),
      rgba(255,255,255,0.18)
    );
    box-shadow: 0 0 8px rgba(160,190,255,0.28);
  }
  .section-line {
    position: relative;
    height: 2px;
    flex: 1;
    background: transparent;
    box-shadow: none;
  }
  .section-caret {
    margin-left: auto;
    color: var(--muted);
    font-size: 14px;
    transform: rotate(0deg);
    transition: transform 120ms ease;
  }
  .section[aria-expanded="false"] .section-caret {
    transform: rotate(-90deg);
  }

  /* ===== Lock overlay ===== */
  .locked .wrap, .locked header, .locked footer {
    filter: blur(10px) brightness(0.85);
    pointer-events: none;
    user-select: none;
  }
  .lock-overlay {
    position: fixed;
    inset: 0;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 18px;
    background: rgba(7,10,14,0.62);
    backdrop-filter: blur(10px);
    z-index: 9999;
  }
  .locked .lock-overlay {
    display: flex;
  }
  .lock-card {
    width: min(560px, 100%);
    border-radius: 16px;
    border: 1px solid rgba(255,255,255,0.10);
    background: rgba(18,24,35,0.88);
    box-shadow: 0 20px 80px rgba(0,0,0,0.55);
    padding: 16px 16px 14px;
  }
  .lock-title {
    font-size: 15px;
    font-weight: 800;
    letter-spacing: 0.02em;
    margin-bottom: 4px;
  }
  .lock-sub {
    color: rgba(154,167,189,0.95);
    font-size: 12px;
    line-height: 1.5;
    margin-bottom: 12px;
  }
  .lock-row {
    display: flex;
    gap: 10px;
    align-items: center;
  }
  .lock-input {
    flex: 1;
    min-width: 0;
    padding: 10px 12px;
    border-radius: 12px;
    border: 1px solid rgba(255,255,255,0.12);
    background: rgba(15,21,32,0.70);
    color: var(--text);
    outline: none;
  }
  .lock-btn {
    padding: 10px 12px;
    border-radius: 12px;
    border: 1px solid rgba(255,255,255,0.12);
    background: rgba(31,42,58,0.85);
    color: var(--text);
    cursor: pointer;
    font-weight: 700;
    font-size: 12px;
  }
  .lock-btn:hover { filter: brightness(1.10); }
  .lock-err {
    margin-top: 10px;
    min-height: 16px;
    font-size: 12px;
    color: rgba(255,92,92,0.95);
  }
  .lock-foot {
    margin-top: 10px;
    color: rgba(154,167,189,0.75);
    font-size: 11px;
  }

  /* ===========================
    Scrollspy sidebar (low-interference)
    - hidden: keep a small handle with ">"
    - hover/click: expand
    =========================== */

  :root{
    --spy-w: 220px;          /* sidebar width when open */
    --spy-handle-w: 22px;    /* visible handle width when hidden */
    --spy-top: 92px;         /* distance from top */
    --spy-z: 999;
  }

  /* container */
  #spyNav{
    position: fixed;
    left: 0;
    top: 50%;
    transform: translateY(-50%) translateX(calc(-1 * (var(--spy-w) - var(--spy-handle-w))));
    width: var(--spy-w);
    max-height: calc(100vh - 48px);
    z-index: var(--spy-z);

    border-radius: 14px;
    border: 1px solid rgba(255,255,255,.10);
    background: rgba(0,0,0,.18);
    backdrop-filter: blur(8px);
    overflow: visible;

    /* default: hidden but handle still visible */
    opacity: 0.10;
    pointer-events: auto;

    transition: transform .18s ease, opacity .18s ease;
  }

  /* open state (expanded) */
  body.spy-open #spyNav{
    transform: translateY(-50%) translateX(0);
    opacity: 0.95;
  }

  /* inside */
  #spyNav .spy-inner{
    display: grid;
    grid-template-columns: 1fr;
  }

  /* handle strip (always on the right edge of sidebar box) */
  #spyNav .spy-handle{
    position: absolute;
    top: 0;
    right: 0;
    width: var(--spy-handle-w);
    height: 100%;

    display: flex;
    align-items: center;
    justify-content: center;

    background: rgba(124,156,255,.18);
    border-left: 1px solid rgba(124,156,255,.35);
    color: rgba(255,255,255,.90);
    font-family: ui-monospace, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
    font-size: 13px;

    cursor: pointer;
    user-select: none;
  }

  body:not(.spy-open) #spyNav{
    opacity: 0.65;
  }

  /* when open, flip handle to "<" */
  body:not(.spy-open) #spyNav .spy-handle{
    background: rgba(124,156,255,.40);
    border-left: 1px solid rgba(124,156,255,.60);
    color: rgba(255,255,255,1);
  }
  body.spy-open #spyNav .spy-handle{
    background: rgba(124,156,255,.14);
    border-left: 1px solid rgba(124,156,255,.28);
    color: rgba(255,255,255,.85);
  }
  body.spy-open #spyNav .spy-handle::after{ content: "<"; }
  body:not(.spy-open) #spyNav .spy-handle::after{ content: ">"; }

  /* list */
  #spyNav .spy-list{
    padding: 10px 10px 10px 10px;
    padding-right: calc(var(--spy-handle-w) + 10px); /* avoid handle overlap */
    overflow: auto;
    max-height: calc(100vh - var(--spy-top) - 24px);
  }

  #spyNav .spy-head{
    font-size: 23px;
    font-weight: 800;
    letter-spacing: 0.10em;
    color: rgba(233,238,247,0.95);
    margin-bottom: 8px;
  }

  #spyNav a.spy-item{
    display: block;
    padding: 7px 10px;
    border-radius: 10px;
    color: rgba(255,255,255,.70);
    text-decoration: none;
    font-size: 12px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  #spyNav a.spy-item:hover{
    background: rgba(255,255,255,.06);
    color: rgba(255,255,255,.88);
  }

  #spyNav a.spy-item.active{
    background: rgba(124,156,255,.28);
    color: rgba(255,255,255,.98);
    border: 1px solid rgba(124,156,255,.45);
  }