:root{
    --ink:#13142b;--ink-2:#0c0d1e;--canvas:#f4f5fa;--surface:#fff;
    --brand:#4b3df0;--brand-deep:#2a1fb0;--brand-tint:#ecebfe;
    --signal:#ff5a3c;--signal-tint:#ffe7e1;--up:#16c073;
    --line:#e6e7ef;--muted:#5d6079;--muted-soft:#8a8da6;--prose:#33344a;
    --radius:18px;--radius-sm:12px;
    --shadow:0 18px 50px -24px rgba(19,20,43,.30);--shadow-soft:0 8px 30px -18px rgba(19,20,43,.35);
    --maxw:1180px;
    --font-display:"Bricolage Grotesque",-apple-system,sans-serif;--font-body:"Plus Jakarta Sans",-apple-system,sans-serif;--font-mono:"JetBrains Mono",ui-monospace,monospace;
  }
  *{box-sizing:border-box;margin:0;padding:0}
  html{scroll-behavior:smooth}
  body{font-family:var(--font-body);background:var(--canvas);color:var(--ink);line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:hidden}
  a{color:inherit;text-decoration:none}
  .wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}
  h1,h2,h3,h4{font-family:var(--font-display);font-weight:700;letter-spacing:-.02em;line-height:1.12}
  .eyebrow{font-family:var(--font-mono);font-size:.74rem;font-weight:700;letter-spacing:.16em;text-transform:uppercase;color:var(--brand)}
  .btn{display:inline-flex;align-items:center;gap:.5rem;font-family:var(--font-body);font-weight:700;font-size:.97rem;padding:.85rem 1.4rem;border-radius:999px;border:0;cursor:pointer;transition:transform .18s,box-shadow .18s,border-color .18s;white-space:nowrap}
  .btn-primary{background:var(--signal);color:#fff;box-shadow:0 10px 24px -10px rgba(255,90,60,.7)}.btn-primary:hover{transform:translateY(-2px)}
  .btn-ghost{background:transparent;color:var(--ink);border:1.5px solid var(--line)}.btn-ghost:hover{border-color:var(--ink);transform:translateY(-2px)}
  .btn-light{background:#fff;color:var(--ink);border:1.5px solid var(--line)}.btn-light:hover{transform:translateY(-2px)}
  .btn-arrow::after{content:"→";transition:transform .2s}.btn-arrow:hover::after{transform:translateX(4px)}

  /* reading progress */
  .progress{position:fixed;top:0;left:0;height:3px;width:0;background:linear-gradient(90deg,var(--brand),var(--signal));z-index:90;transition:width .1s}

  header{position:sticky;top:0;z-index:60;background:rgba(244,245,250,.85);backdrop-filter:blur(12px);border-bottom:1px solid transparent;transition:.2s}
  header.scrolled{border-bottom-color:var(--line);background:rgba(244,245,250,.94)}
  .nav{display:flex;align-items:center;justify-content:space-between;height:74px}
  .logo{display:flex;align-items:center;gap:.55rem;font-family:var(--font-display);font-weight:800;font-size:1.4rem;letter-spacing:-.03em}
  .logo .mark{width:30px;height:30px;border-radius:9px;background:var(--brand);display:grid;place-items:center;flex:none}
  .logo .mark::after{content:"";width:11px;height:11px;border:2.5px solid #fff;border-radius:50%;box-shadow:6px 6px 0 -1px var(--signal)}
  .logo b{color:var(--brand)}
  .nav-links{display:flex;align-items:center;gap:1.7rem;list-style:none}
  .nav-links a{font-weight:600;font-size:.95rem;transition:color .15s}.nav-links a:hover,.nav-links a.active{color:var(--brand)}
  .has-drop{position:relative}.has-drop>a::after{content:"▾";font-size:.7rem;margin-left:.3rem;color:var(--muted-soft)}
  .drop{position:absolute;top:140%;left:50%;transform:translateX(-50%) translateY(8px);background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:var(--shadow);padding:10px;min-width:300px;opacity:0;visibility:hidden;transition:.2s}
  .has-drop:hover .drop,.has-drop:focus-within .drop{opacity:1;visibility:visible;transform:translateX(-50%) translateY(0)}
  .drop a{display:flex;flex-direction:column;gap:1px;padding:.6rem .8rem;border-radius:10px}
  .drop a:hover{background:var(--brand-tint)}
  .drop a span{font-weight:700;font-size:.92rem}.drop a small{color:var(--muted-soft);font-weight:500;font-size:.8rem}
  .nav-cta{display:flex;align-items:center;gap:1rem}
  .menu-toggle{display:none;background:none;border:0;cursor:pointer;width:42px;height:42px}
  .menu-toggle span{display:block;width:22px;height:2px;background:var(--ink);margin:5px auto}

  /* Article header */
  .art-head{padding:44px 0 30px}
  .crumb{font-family:var(--font-mono);font-size:.76rem;color:var(--muted-soft);margin-bottom:22px}
  .crumb a:hover{color:var(--brand)}.crumb span{color:var(--ink)}
  .cat-pill{display:inline-block;font-family:var(--font-mono);font-size:.7rem;font-weight:700;letter-spacing:.12em;text-transform:uppercase;color:var(--brand);background:var(--brand-tint);padding:.35rem .8rem;border-radius:999px}
  .art-head h1{font-size:clamp(2.1rem,4.6vw,3.3rem);font-weight:800;margin:18px 0 16px;max-width:20ch}
  .art-dek{font-size:1.22rem;color:var(--muted);max-width:62ch;line-height:1.55}
  .byline{display:flex;align-items:center;gap:14px;margin-top:26px;flex-wrap:wrap}
  .byline .av{width:46px;height:46px;border-radius:50%;background:linear-gradient(135deg,var(--brand),var(--signal));flex:none}
  .byline .who b{font-size:.95rem}.byline .who b a:hover{color:var(--brand)}
  .byline .who .meta{font-size:.84rem;color:var(--muted-soft);font-family:var(--font-mono)}
  .byline .share{margin-left:auto;display:flex;gap:8px}
  .byline .share a{width:38px;height:38px;border-radius:50%;border:1px solid var(--line);background:#fff;display:grid;place-items:center;color:var(--muted);font-size:.9rem;font-weight:700;transition:.18s}
  .byline .share a:hover{border-color:var(--brand);color:var(--brand);transform:translateY(-2px)}

  .feat{max-width:var(--maxw);margin:0 auto;padding:0 24px}
  .feat .ph{height:clamp(220px,38vw,440px);border-radius:24px;background:linear-gradient(135deg,#2a1fb0,#4b3df0 55%,#ff5a3c);position:relative;overflow:hidden;display:grid;place-items:center}
  .feat .ph::before{content:"";position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.08) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.08) 1px,transparent 1px);background-size:40px 40px;mask-image:radial-gradient(70% 70% at 50% 50%,#000,transparent)}
  .feat .ph span{position:relative;font-family:var(--font-mono);font-size:.8rem;color:rgba(255,255,255,.8);border:1px dashed rgba(255,255,255,.5);padding:.5rem 1rem;border-radius:8px}

  /* Layout: TOC + content */
  .post-wrap{max-width:1060px;margin:0 auto;padding:50px 24px 40px}
  .post-grid{display:grid;grid-template-columns:240px minmax(0,1fr);gap:54px;align-items:start}
  .toc{position:sticky;top:100px}
  .toc .lbl{font-family:var(--font-mono);font-size:.72rem;font-weight:700;letter-spacing:.14em;text-transform:uppercase;color:var(--muted-soft);margin-bottom:14px}
  .toc ul{list-style:none}
  .toc li{margin-bottom:2px}
  .toc a{display:block;font-size:.88rem;color:var(--muted);padding:.4rem .8rem;border-left:2px solid var(--line);transition:.15s;line-height:1.35}
  .toc a:hover{color:var(--ink);border-left-color:var(--muted-soft)}
  .toc a.active{color:var(--brand);border-left-color:var(--brand);font-weight:600}
  .toc-m{display:none}

  /* Prose */
  .prose{max-width:720px}
  .prose>p{font-size:1.08rem;line-height:1.78;color:var(--prose);margin:0 0 1.35rem}
  .prose .lead{font-size:1.3rem;line-height:1.6;color:var(--ink);font-weight:500;margin-bottom:1.6rem}
  .prose h2{font-size:clamp(1.5rem,2.6vw,1.95rem);margin:2.8rem 0 1rem;scroll-margin-top:96px}
  .prose h3{font-size:1.25rem;margin:1.9rem 0 .6rem}
  .prose ul,.prose ol{margin:0 0 1.35rem;padding-left:1.3rem}
  .prose li{font-size:1.06rem;line-height:1.7;color:var(--prose);margin-bottom:.55rem}
  .prose strong{color:var(--ink);font-weight:700}
  .prose a{color:var(--brand);font-weight:600;text-decoration:underline;text-decoration-color:var(--brand-tint);text-underline-offset:3px}
  .prose a:hover{text-decoration-color:var(--brand)}
  .prose blockquote{margin:1.8rem 0;padding:.4rem 0 .4rem 1.6rem;border-left:3px solid var(--brand);font-size:1.22rem;line-height:1.5;font-family:var(--font-display);color:var(--ink)}
  .prose figure{margin:2rem 0}
  .prose figure .ph{height:240px;border-radius:16px;background:linear-gradient(135deg,var(--brand-tint),#fff);border:1px solid var(--line);display:grid;place-items:center;color:var(--muted-soft);font-family:var(--font-mono);font-size:.78rem}
  .prose figcaption{text-align:center;font-size:.84rem;color:var(--muted-soft);margin-top:10px}
  .prose hr{border:0;border-top:1px solid var(--line);margin:2.4rem 0}

  /* Callout / key takeaways */
  .callout{background:var(--brand-tint);border:1px solid #d9d6fb;border-radius:16px;padding:24px 26px;margin:2rem 0}
  .callout b{display:flex;align-items:center;gap:.5rem;font-family:var(--font-display);font-size:1.05rem;margin-bottom:.6rem}
  .callout b::before{content:"✦";color:var(--brand)}
  .callout ul{margin:0;padding-left:1.2rem}
  .callout li{font-size:1rem;margin-bottom:.4rem;color:var(--prose)}

  /* Table */
  .prose .tablewrap{overflow-x:auto;margin:1.8rem 0}
  .prose table{width:100%;border-collapse:collapse;font-size:.94rem;min-width:440px}
  .prose th{text-align:left;background:var(--ink);color:#fff;padding:.7rem .9rem;font-family:var(--font-display);font-weight:600;font-size:.9rem}
  .prose th:first-child{border-radius:10px 0 0 0}.prose th:last-child{border-radius:0 10px 0 0}
  .prose td{padding:.7rem .9rem;border-bottom:1px solid var(--line);color:var(--prose)}
  .prose tr:nth-child(even) td{background:var(--surface)}

  /* in-article CTA */
  .inline-cta{background:var(--ink);color:#fff;border-radius:18px;padding:28px 30px;margin:2.4rem 0;display:flex;align-items:center;gap:24px;flex-wrap:wrap}
  .inline-cta div{flex:1;min-width:220px}
  .inline-cta b{font-family:var(--font-display);font-size:1.2rem;display:block;margin-bottom:.3rem;color:#fff}
  .inline-cta p{color:#aeb0d0;font-size:.92rem}

  /* tags */
  .tags{display:flex;gap:8px;flex-wrap:wrap;margin:2.4rem 0 0}
  .tags a{font-family:var(--font-mono);font-size:.78rem;background:var(--surface);border:1px solid var(--line);color:var(--muted);padding:.35rem .8rem;border-radius:999px}
  .tags a:hover{border-color:var(--brand);color:var(--brand)}

  /* author bio */
  .author-bio{max-width:720px;margin:40px auto 0;background:var(--surface);border:1px solid var(--line);border-radius:20px;padding:28px;display:flex;gap:20px;align-items:flex-start}
  .author-bio .av{width:64px;height:64px;border-radius:50%;background:linear-gradient(135deg,var(--brand),var(--signal));flex:none}
  .author-bio .lbl{font-family:var(--font-mono);font-size:.7rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted-soft);margin-bottom:4px}
  .author-bio h3{font-size:1.2rem;margin-bottom:.4rem}
  .author-bio h3 a:hover{color:var(--brand)}
  .author-bio p{color:var(--muted);font-size:.93rem;margin-bottom:.7rem}
  .author-bio .lk{font-weight:700;font-size:.85rem;color:var(--brand)}

  /* related */
  .related{background:var(--surface);border-top:1px solid var(--line);padding:72px 0}
  .related .sec-head{max-width:680px;margin-bottom:36px}
  .related .eyebrow{margin-bottom:.4rem;display:block}
  .related h2{font-size:clamp(1.5rem,3vw,2.1rem)}
  .cards{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
  .pcard{background:var(--canvas);border:1px solid var(--line);border-radius:18px;overflow:hidden;transition:.2s;display:flex;flex-direction:column}
  .pcard:hover{box-shadow:var(--shadow);transform:translateY(-4px)}
  .pcard .thumb{height:150px;background:linear-gradient(135deg,var(--brand-tint),#fff);position:relative}
  .pcard .thumb.v2{background:linear-gradient(135deg,#ffe7e1,#fff)}
  .pcard .thumb.v3{background:linear-gradient(135deg,#dff6ec,#fff)}
  .pcard .thumb .c{position:absolute;top:12px;left:12px;font-family:var(--font-mono);font-size:.64rem;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--brand);background:#fff;padding:.25rem .6rem;border-radius:999px}
  .pcard .b{padding:20px;flex:1;display:flex;flex-direction:column}
  .pcard h3{font-size:1.08rem;line-height:1.25;margin-bottom:.5rem}
  .pcard p{color:var(--muted);font-size:.88rem;flex:1}
  .pcard .m{font-family:var(--font-mono);font-size:.74rem;color:var(--muted-soft);margin-top:12px}

  .cta-band{background:radial-gradient(110% 140% at 20% 0%,#1c1d44,var(--ink-2));color:#fff;text-align:center;border-radius:28px;padding:60px 32px;margin:40px auto 0;max-width:840px}
  .cta-band h2{font-size:clamp(1.6rem,3.4vw,2.3rem);max-width:24ch;margin:0 auto 1rem;color:#fff}
  .cta-band p{color:#bcbedd;max-width:46ch;margin:0 auto 24px}

  footer{background:var(--ink-2);color:#c7c8e0;padding:72px 0 30px;margin-top:20px}
  .foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr 1.2fr;gap:36px;padding-bottom:48px;border-bottom:1px solid rgba(255,255,255,.1)}
  .foot-brand .logo{color:#fff;margin-bottom:14px}.foot-brand p{font-size:.9rem;color:#9a9cc0;max-width:34ch}
  footer h4{font-family:var(--font-display);font-size:.95rem;color:#fff;margin-bottom:16px}
  footer ul{list-style:none}footer li{margin-bottom:10px}footer li a{font-size:.88rem;color:#a7a9c8}footer li a:hover{color:#fff}
  .foot-bottom{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:12px;padding-top:24px;font-size:.82rem;color:#777aa0}

  @media (max-width:980px){
    .post-grid{grid-template-columns:1fr;gap:0}
    .toc{display:none}
    .toc-m{display:block;margin-bottom:28px;background:var(--surface);border:1px solid var(--line);border-radius:14px;overflow:hidden}
    .toc-m summary{list-style:none;cursor:pointer;padding:16px 20px;font-family:var(--font-display);font-weight:700;font-size:1rem;display:flex;justify-content:space-between}
    .toc-m summary::-webkit-details-marker{display:none}
    .toc-m summary::after{content:"+";color:var(--brand);font-family:var(--font-mono)}
    .toc-m[open] summary::after{content:"–"}
    .toc-m ul{list-style:none;padding:0 20px 16px}
    .toc-m li{margin-bottom:8px}.toc-m a{font-size:.92rem;color:var(--muted)}
    .cards{grid-template-columns:1fr}
    .foot-grid{grid-template-columns:1fr 1fr;gap:30px}
  }
  @media (max-width:680px){
    .nav-links{position:fixed;inset:74px 0 auto 0;flex-direction:column;background:#fff;border-bottom:1px solid var(--line);padding:20px 24px;gap:8px;align-items:stretch;display:none;box-shadow:var(--shadow)}
    .nav-links.open{display:flex}
    .has-drop .drop{position:static;opacity:1;visibility:visible;transform:none;box-shadow:none;border:0;padding:0 0 0 14px;min-width:0}
    .has-drop>a::after{display:none}.menu-toggle{display:block}.nav-cta .btn-ghost{display:none}
    .author-bio{flex-direction:column;gap:14px}.foot-grid{grid-template-columns:1fr}
  }
  @media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;scroll-behavior:auto}}
  :focus-visible{outline:3px solid var(--signal);outline-offset:2px;border-radius:4px}