:root {
    --ink: #0a0f14;
    --ink-2: #0f1620;
    --surface: #131c27;
    --surface-2: #1a2532;
    --surface-3: #233040;
    --border: #243345;
    --border-soft: #1b2532;
    --text: #e8edf3;
    --text-soft: #b4c2d0;
    --text-mute: #7e8e9d;
    --flow: #14b8a6;       /* caught / handled / healthy */
    --flow-2: #06b6d4;
    --fire: #f59e0b;       /* warning / in-flight */
    --fire-2: #fb923c;
    --danger: #ef4444;     /* thrown / uncaught */
    --danger-2: #f87171;
    --success: #22c55e;
    --violet: #a78bfa;     /* the external sink: PostHog */
    --serif: 'Fraunces', Georgia, serif;
    --sans: 'Manrope', system-ui, sans-serif;
    --mono: 'JetBrains Mono', ui-monospace, monospace;
  }

  * { box-sizing: border-box; margin: 0; padding: 0; }
  html { scroll-behavior: smooth; }
  body {
    font-family: var(--sans);
    background: var(--ink);
    color: var(--text);
    line-height: 1.6;
    font-size: 16px;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
  }

  :focus-visible { outline: 2px solid var(--flow); outline-offset: 2px; border-radius: 4px; }

  .bg-deco {
    position: fixed; inset: 0; z-index: -1; pointer-events: none;
    background:
      radial-gradient(ellipse 80% 50% at 50% -10%, rgba(239, 68, 68, 0.06), transparent 60%),
      radial-gradient(ellipse 60% 40% at 100% 60%, rgba(20, 184, 166, 0.05), transparent 60%),
      var(--ink);
  }
  .bg-deco::before {
    content: ''; position: absolute; inset: 0;
    background-image:
      linear-gradient(rgba(36, 51, 69, 0.22) 1px, transparent 1px),
      linear-gradient(90deg, rgba(36, 51, 69, 0.22) 1px, transparent 1px);
    background-size: 64px 64px;
    mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, black 30%, transparent 80%);
  }

  .wrap { max-width: 1240px; margin: 0 auto; padding: 0 32px; }

  /* ===== Shared site bar ===== */
  .sitebar { position: sticky; top: 0; z-index: 60; backdrop-filter: blur(14px); background: rgba(10, 15, 20, 0.85); border-bottom: 1px solid var(--border-soft); }
  .sitebar-inner { max-width: 1240px; margin: 0 auto; padding: 12px 32px; display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
  .site-brand { display: flex; align-items: center; gap: 10px; font-family: var(--serif); font-weight: 600; font-style: italic; font-size: 16px; color: var(--text); text-decoration: none; white-space: nowrap; }
  .site-mark { width: 24px; height: 24px; border-radius: 7px; background: linear-gradient(135deg, var(--flow), #6366f1); position: relative; overflow: hidden; flex-shrink: 0; }
  .site-mark::after { content: ''; position: absolute; inset: 0; background: radial-gradient(circle at 30% 30%, rgba(255,255,255,0.5), transparent 60%); }
  .site-links { display: flex; gap: 4px; flex-wrap: wrap; }
  .site-links a { font-family: var(--sans); font-size: 13px; color: var(--text-mute); text-decoration: none; padding: 6px 12px; border-radius: 8px; transition: all 0.18s; white-space: nowrap; }
  .site-links a:hover { color: var(--text); background: rgba(255,255,255,0.04); }
  .site-links a.active { color: var(--flow); background: rgba(20,184,166,0.1); font-weight: 600; }
  @media (max-width: 720px) { .site-links a { padding: 6px 9px; font-size: 12px; } .site-brand span:not(.site-mark) { display: none; } }

  /* Top bar */
  .topbar {
    position: sticky; top: 0; z-index: 50;
    backdrop-filter: blur(14px);
    background: rgba(10, 15, 20, 0.78);
    border-bottom: 1px solid var(--border-soft);
  }
  .topbar-inner {
    display: flex; align-items: center; justify-content: space-between;
    padding: 14px 32px; max-width: 1240px; margin: 0 auto; gap: 24px; flex-wrap: wrap;
  }
  .brand {
    display: flex; align-items: center; gap: 12px;
    font-family: var(--serif); font-weight: 600; font-style: italic; font-size: 18px;
  }
  .brand-mark {
    width: 28px; height: 28px; border-radius: 8px;
    background: linear-gradient(135deg, var(--danger), var(--fire));
    position: relative; overflow: hidden;
  }
  .brand-mark::after {
    content: ''; position: absolute; inset: 0;
    background: radial-gradient(circle at 30% 30%, rgba(255,255,255,0.5), transparent 60%);
  }
  .topnav { display: flex; gap: 20px; font-size: 13px; color: var(--text-soft); flex-wrap: wrap; }
  .topnav a { color: inherit; text-decoration: none; transition: color 0.2s; }
  .topnav a:hover { color: var(--flow); }
  @media (max-width: 980px) { .topnav { display: none; } }

  /* Hero */
  .hero { padding: 96px 0 72px; position: relative; }
  .eyebrow {
    display: inline-flex; align-items: center; gap: 10px;
    padding: 6px 14px; border: 1px solid var(--border); border-radius: 999px;
    font-family: var(--mono); font-size: 11px; letter-spacing: 0.1em;
    text-transform: uppercase; color: var(--text-soft); margin-bottom: 32px;
  }
  .eyebrow::before {
    content: ''; width: 6px; height: 6px; border-radius: 50%;
    background: var(--danger); box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.15);
  }
  h1.title {
    font-family: var(--serif); font-weight: 500;
    font-size: clamp(44px, 6.6vw, 90px); line-height: 0.98;
    letter-spacing: -0.04em; margin-bottom: 28px;
  }
  h1.title em { font-style: italic; font-weight: 400; color: var(--flow); }
  h1.title .struck { color: var(--danger); font-style: italic; font-weight: 400; }
  .lede {
    font-size: clamp(18px, 1.6vw, 22px); color: var(--text-soft);
    max-width: 700px; line-height: 1.5; margin-bottom: 40px;
  }
  .hero-meta {
    display: flex; gap: 40px; flex-wrap: wrap;
    padding-top: 32px; border-top: 1px solid var(--border-soft);
  }
  .meta-item .label {
    font-family: var(--mono); font-size: 10px; letter-spacing: 0.1em;
    text-transform: uppercase; color: var(--text-mute); margin-bottom: 4px;
  }
  .meta-item .value { font-family: var(--serif); font-size: 18px; color: var(--text); }

  /* Hero net motif */
  .net-motif {
    position: relative; height: 120px; margin: 8px 0 8px;
    border-bottom: 1px dashed var(--flow);
    overflow: hidden;
  }
  .net-motif .net-label {
    position: absolute; right: 0; bottom: 6px;
    font-family: var(--mono); font-size: 10px; letter-spacing: 0.15em;
    color: var(--flow); text-transform: uppercase; opacity: 0.7;
  }
  .net-motif .drop {
    position: absolute; top: -14px; width: 10px; height: 10px; border-radius: 50%;
    background: var(--danger);
    animation: fall 3.6s ease-in infinite;
  }
  .net-motif .drop.d1 { left: 14%; animation-delay: 0s; }
  .net-motif .drop.d2 { left: 44%; animation-delay: 1.2s; background: var(--fire); }
  .net-motif .drop.d3 { left: 74%; animation-delay: 2.4s; }
  @keyframes fall {
    0%   { transform: translateY(0); opacity: 0; }
    10%  { opacity: 1; }
    62%  { transform: translateY(104px); opacity: 1; }
    74%  { transform: translateY(94px); opacity: 1; }   /* bounce off the net */
    100% { transform: translateY(100px); opacity: 0; }
  }

  /* Sections */
  section.chapter { padding: 96px 0; position: relative; }
  .chapter-num {
    font-family: var(--mono); font-size: 12px; letter-spacing: 0.15em;
    color: var(--danger); margin-bottom: 16px;
    display: flex; align-items: center; gap: 12px;
  }
  .chapter-num::after {
    content: ''; flex: 1; height: 1px;
    background: linear-gradient(to right, var(--danger), transparent); opacity: 0.35;
  }
  h2.chapter-title {
    font-family: var(--serif); font-weight: 500;
    font-size: clamp(34px, 4.4vw, 54px); line-height: 1.02;
    letter-spacing: -0.03em; margin-bottom: 24px; max-width: 820px;
  }
  h2.chapter-title em { font-style: italic; color: var(--flow); font-weight: 400; }
  .chapter-intro {
    font-size: 18px; color: var(--text-soft); max-width: 740px; margin-bottom: 48px;
  }
  h3 {
    font-family: var(--serif); font-weight: 500; font-size: 27px;
    letter-spacing: -0.02em; margin: 40px 0 16px;
  }
  h4 {
    font-family: var(--sans); font-weight: 600;
    font-size: 12px; letter-spacing: 0.1em; text-transform: uppercase;
    color: var(--flow); margin: 28px 0 12px;
  }
  p { margin-bottom: 16px; color: var(--text-soft); }
  p strong { color: var(--text); font-weight: 600; }

  /* Code blocks (pre preserves whitespace) */
  pre.code-block {
    background: var(--ink-2); border: 1px solid var(--border);
    border-radius: 12px; padding: 24px 28px;
    font-family: var(--mono); font-size: 13px; line-height: 1.7;
    overflow-x: auto; margin: 16px 0; position: relative;
    white-space: pre; color: var(--text-soft); tab-size: 2;
  }
  pre.code-block::before {
    content: attr(data-lang);
    position: absolute; top: 12px; right: 16px;
    font-size: 10px; color: var(--text-mute);
    letter-spacing: 0.1em; text-transform: uppercase;
    background: var(--ink-2); padding: 2px 4px;
  }
  pre.code-block .kw   { color: #c084fc; }
  pre.code-block .typ  { color: var(--flow); }
  pre.code-block .str  { color: var(--fire-2); }
  pre.code-block .num  { color: #fbbf24; }
  pre.code-block .com  { color: var(--text-mute); font-style: italic; }
  pre.code-block .fn   { color: #60a5fa; }
  pre.code-block .anno { color: var(--success); }
  pre.code-block .err  { color: var(--danger-2); }

  /* Two-up cards */
  .two-up {
    display: grid; grid-template-columns: 1fr 1fr; gap: 32px; margin: 32px 0;
  }
  @media (max-width: 760px) { .two-up { grid-template-columns: 1fr; } }
  .card {
    padding: 32px; background: var(--surface);
    border: 1px solid var(--border); border-radius: 16px; position: relative;
  }
  .card.bad  { border-color: rgba(239, 68, 68, 0.3); }
  .card.good { border-color: rgba(20, 184, 166, 0.3); }
  .card-tag {
    font-family: var(--mono); font-size: 10px; text-transform: uppercase;
    letter-spacing: 0.1em; color: var(--danger); margin-bottom: 8px;
  }
  .card.good .card-tag { color: var(--flow); }
  .card-title { font-family: var(--serif); font-size: 22px; margin-bottom: 12px; }

  /* Taxonomy explorer */
  .tax-wrap {
    display: grid; grid-template-columns: 0.85fr 1.15fr; gap: 28px;
    align-items: start; margin: 32px 0;
  }
  @media (max-width: 900px) { .tax-wrap { grid-template-columns: 1fr; } }
  .tax-list { display: flex; flex-direction: column; gap: 8px; }
  .tax-item {
    text-align: left; background: var(--surface);
    border: 1px solid var(--border); color: var(--text);
    padding: 16px 18px; border-radius: 12px;
    font-family: var(--sans); font-size: 14px; cursor: pointer;
    transition: all 0.2s; display: flex; flex-direction: column; gap: 3px;
  }
  .tax-item .ti-name { font-weight: 600; }
  .tax-item .ti-sub { font-size: 12px; color: var(--text-mute); font-family: var(--mono); }
  .tax-item:hover { border-color: var(--flow); }
  .tax-item.active { border-color: var(--danger); background: rgba(239, 68, 68, 0.06); }
  .tax-item.active .ti-name { color: var(--danger-2); }
  .tax-panel {
    background: var(--surface); border: 1px solid var(--border);
    border-radius: 16px; padding: 28px; position: sticky; top: 90px;
  }
  .tax-panel .scope-pill {
    display: inline-block; font-family: var(--mono); font-size: 10px;
    padding: 4px 10px; border-radius: 6px; margin-bottom: 12px;
    letter-spacing: 0.1em; text-transform: uppercase;
  }
  .scope-pill.local { background: rgba(20,184,166,0.15); color: var(--flow); }
  .scope-pill.global { background: rgba(239,68,68,0.15); color: var(--danger-2); }
  .scope-pill.design { background: rgba(167,139,250,0.15); color: var(--violet); }
  .tax-panel h4.tp-title {
    margin: 0 0 6px; color: var(--text); font-family: var(--serif);
    font-size: 22px; text-transform: none; letter-spacing: -0.01em;
  }
  .tax-panel .tp-catch {
    font-family: var(--mono); font-size: 13px; color: var(--flow); margin-bottom: 14px;
  }
  .tax-panel p { font-size: 14px; }
  .tax-panel pre.code-block { margin-top: 16px; }

  /* Pipeline simulator */
  .demo {
    margin: 32px 0; border: 1px solid var(--border);
    border-radius: 18px; overflow: hidden; background: var(--surface);
  }
  .demo-head {
    display: flex; align-items: center; justify-content: space-between;
    padding: 16px 24px; border-bottom: 1px solid var(--border-soft); background: var(--ink-2);
  }
  .demo-head .dot-group { display: flex; gap: 6px; }
  .demo-head .dot { width: 10px; height: 10px; border-radius: 50%; background: var(--surface-3); }
  .demo-head .title-pill {
    font-family: var(--mono); font-size: 11px;
    letter-spacing: 0.1em; color: var(--text-mute); text-transform: uppercase;
  }
  .demo-grid { display: grid; grid-template-columns: 1fr 1fr; }
  @media (max-width: 900px) { .demo-grid { grid-template-columns: 1fr; } }
  .demo-pane { padding: 28px; }
  .demo-pane.left {
    border-right: 1px solid var(--border-soft);
    background: radial-gradient(ellipse at top, rgba(239,68,68,0.05), transparent 60%), var(--ink-2);
  }
  @media (max-width: 900px) {
    .demo-pane.left { border-right: none; border-bottom: 1px solid var(--border-soft); }
  }

  .source-picker { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 22px; }

  .pipe { display: flex; flex-direction: column; gap: 0; }
  .station {
    position: relative; padding: 16px 18px;
    background: var(--ink); border: 1px solid var(--border); border-radius: 12px;
    transition: all 0.35s;
  }
  .station + .station { margin-top: 26px; }
  .station::after {
    content: ''; position: absolute; left: 50%; bottom: -22px;
    width: 2px; height: 18px; background: var(--border);
    transform: translateX(-50%); transition: background 0.35s;
  }
  .station:last-child::after { display: none; }
  .station .st-kicker {
    font-family: var(--mono); font-size: 9px; letter-spacing: 0.15em;
    text-transform: uppercase; color: var(--text-mute); margin-bottom: 4px;
  }
  .station .st-main {
    font-family: var(--mono); font-size: 13px; color: var(--text-soft);
  }
  .station .st-sub { font-size: 11px; color: var(--text-mute); margin-top: 2px; }
  .station.lit {
    border-color: var(--danger); background: rgba(239,68,68,0.1);
    box-shadow: 0 0 20px rgba(239,68,68,0.18);
  }
  .station.lit .st-kicker { color: var(--danger-2); }
  .station.lit.converge { border-color: var(--flow); background: rgba(20,184,166,0.1); box-shadow: 0 0 20px rgba(20,184,166,0.18); }
  .station.lit.converge .st-kicker { color: var(--flow); }
  .station.lit.sink { border-color: var(--violet); background: rgba(167,139,250,0.1); box-shadow: 0 0 20px rgba(167,139,250,0.18); }
  .station.lit.sink .st-kicker { color: var(--violet); }
  .station.lit::after { background: var(--danger); }

  /* Event card (mock PostHog event) */
  .event-card {
    background: #07101a; border: 1px solid var(--border);
    border-radius: 14px; padding: 0; overflow: hidden;
    opacity: 0.35; transition: opacity 0.4s;
  }
  .event-card.live { opacity: 1; border-color: rgba(167,139,250,0.4); }
  .event-head {
    display: flex; align-items: center; justify-content: space-between;
    padding: 12px 16px; border-bottom: 1px solid var(--border-soft);
    background: rgba(167,139,250,0.06);
  }
  .event-head .eh-title {
    font-family: var(--mono); font-size: 12px; color: var(--violet); font-weight: 600;
  }
  .event-head .eh-badge {
    font-family: var(--mono); font-size: 9px; letter-spacing: 0.1em; text-transform: uppercase;
    color: var(--text-mute);
  }
  .event-body { padding: 14px 16px; font-family: var(--mono); font-size: 11.5px; line-height: 1.9; }
  .ev-row { display: flex; gap: 10px; }
  .ev-key { color: var(--text-mute); min-width: 128px; }
  .ev-val { color: var(--text-soft); word-break: break-word; }
  .ev-val.type { color: var(--danger-2); }
  .ev-val.str { color: var(--fire-2); }
  .ev-frame { color: var(--flow); }
  .ev-divider { height: 1px; background: var(--border-soft); margin: 10px 0; }
  .ev-issue {
    display: inline-flex; align-items: center; gap: 6px;
    font-size: 10px; padding: 3px 8px; border-radius: 5px;
    background: rgba(167,139,250,0.12); color: var(--violet); margin-top: 4px;
  }

  /* Console */
  .console {
    background: #050a10; border: 1px solid var(--border); border-radius: 12px;
    padding: 14px 16px; font-family: var(--mono); font-size: 11px; line-height: 1.7;
    height: 120px; overflow-y: auto; color: var(--text-soft); margin-top: 20px;
  }
  .console .log-time { color: var(--text-mute); }
  .console .log-tag { color: var(--danger-2); }
  .console .log-tag.catch { color: var(--fire); }
  .console .log-tag.log { color: var(--flow); }
  .console .log-tag.sink { color: var(--violet); }
  .console .log-line { opacity: 0; animation: logIn 0.3s forwards; }
  @keyframes logIn { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: translateY(0); } }

  /* Buttons */
  .btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 10px 20px; background: var(--flow); color: var(--ink);
    border: none; border-radius: 10px; font-family: var(--sans);
    font-weight: 600; font-size: 14px; cursor: pointer; transition: all 0.2s;
  }
  .btn:hover { background: var(--flow-2); transform: translateY(-1px); }
  .btn:active { transform: translateY(0); }
  .btn.ghost { background: transparent; color: var(--text-soft); border: 1px solid var(--border); }
  .btn.ghost:hover { border-color: var(--flow); color: var(--flow); background: rgba(20,184,166,0.05); }
  .btn.danger { background: var(--danger); color: white; }
  .btn.danger:hover { background: #dc2626; }
  .btn.small { padding: 8px 14px; font-size: 12px; }

  /* Local toggle (throw vs result) */
  .toggle-scope .toggle-head {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 4px; padding-left: 14px; background: var(--ink-2);
    border: 1px solid var(--border); border-radius: 10px; margin: 8px 0 4px;
  }
  .toggle-scope .toggle-head .lbl {
    font-family: var(--mono); font-size: 10px; color: var(--text-mute);
    letter-spacing: 0.15em; text-transform: uppercase; margin-right: 4px;
  }
  .toggle-scope .toggle-head button {
    background: transparent; border: none; color: var(--text-mute);
    padding: 6px 12px; border-radius: 6px; font-family: var(--mono);
    font-size: 11px; cursor: pointer; transition: all 0.2s; white-space: nowrap;
  }
  .toggle-scope .toggle-head button:hover { color: var(--text); }
  .toggle-scope .toggle-head button.active { background: var(--flow); color: var(--ink); font-weight: 600; }
  .toggle-scope .show-throw, .toggle-scope .show-result { display: none; }
  .toggle-scope[data-mode="throw"] .show-throw { display: block; }
  .toggle-scope[data-mode="result"] .show-result { display: block; }

  /* Ref-style table */
  .ref-table { width: 100%; border-collapse: separate; border-spacing: 0; margin: 24px 0; font-size: 14px; }
  .ref-table th, .ref-table td {
    text-align: left; padding: 15px 18px;
    border-bottom: 1px solid var(--border-soft); vertical-align: top;
  }
  .ref-table th {
    font-family: var(--mono); font-size: 11px; color: var(--text-mute);
    text-transform: uppercase; letter-spacing: 0.1em; font-weight: 500;
    border-bottom: 1px solid var(--border);
  }
  .ref-table td:first-child { font-family: var(--mono); font-size: 12.5px; color: var(--flow); width: 38%; }
  .ref-table td { color: var(--text-soft); }

  /* Pitfalls */
  .pitfall {
    padding: 22px 26px; border-left: 3px solid var(--danger);
    background: rgba(239,68,68,0.04); border-radius: 0 12px 12px 0; margin: 16px 0;
  }
  .pitfall .tag {
    font-family: var(--mono); font-size: 10px; text-transform: uppercase;
    letter-spacing: 0.15em; color: var(--danger-2); margin-bottom: 6px;
  }
  .pitfall h4 {
    color: var(--text); font-family: var(--serif); text-transform: none;
    letter-spacing: -0.01em; font-size: 18px; margin: 0 0 8px;
  }
  .pitfall p { font-size: 14px; margin: 0; }

  /* Callout */
  .callout {
    background: var(--surface); border: 1px solid var(--border);
    border-left: 3px solid var(--flow); border-radius: 0 12px 12px 0;
    padding: 20px 24px; margin: 24px 0;
  }
  .callout.warn { border-left-color: var(--fire); }
  .callout .co-tag {
    font-family: var(--mono); font-size: 10px; text-transform: uppercase;
    letter-spacing: 0.15em; color: var(--flow); margin-bottom: 8px;
  }
  .callout.warn .co-tag { color: var(--fire); }
  .callout p { font-size: 14px; margin: 0; color: var(--text-soft); }
  .callout p + p { margin-top: 10px; }

  ul.bullet { list-style: none; margin: 16px 0; }
  ul.bullet li {
    padding-left: 24px; position: relative; margin-bottom: 10px;
    color: var(--text-soft); font-size: 15px;
  }
  ul.bullet li::before {
    content: ''; position: absolute; left: 0; top: 10px;
    width: 8px; height: 8px; border: 1px solid var(--flow); transform: rotate(45deg);
  }

  .inline-code {
    font-family: var(--mono); font-size: 0.9em;
    background: var(--surface-2); padding: 2px 6px; border-radius: 4px; color: var(--flow);
  }

  .divider {
    height: 1px; background: linear-gradient(to right, transparent, var(--border), transparent);
    margin: 56px 0;
  }

  footer {
    padding: 80px 0 60px; border-top: 1px solid var(--border-soft);
    margin-top: 56px; text-align: center;
  }
  footer .closer {
    font-family: var(--serif); font-style: italic; font-size: 27px;
    color: var(--text); max-width: 600px; margin: 0 auto 24px; line-height: 1.3;
  }
  footer .signoff {
    font-family: var(--mono); font-size: 11px; color: var(--text-mute);
    letter-spacing: 0.1em; text-transform: uppercase;
  }

  @media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
      animation-duration: 0.001ms !important;
      animation-iteration-count: 1 !important;
      transition-duration: 0.001ms !important;
    }
  }