:root{
  --bg:#0E1114; --surface:#151A1F; --surface2:#1C232A; --text:#EDF1F3; --muted:#93A0AA;
  --accent:#1FE3C2; --accent2:#12B7C9; --border:#28323B; --ink:#06110F;
  --wrap:1120px; --content:720px; --side:300px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--text);line-height:1.7;-webkit-font-smoothing:antialiased;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background-image:radial-gradient(1200px 620px at 50% -8%, rgba(31,227,194,.06), transparent 70%);
  background-attachment:fixed;background-repeat:no-repeat}
a{color:inherit;text-decoration:none}
img{max-width:100%}
em{font-style:normal;color:var(--accent);font-weight:700}
.mark{display:inline-flex;align-items:center;justify-content:center;width:1.7em;height:1.7em;border-radius:8px;
  background:#0a0f12;border:1px solid var(--border);color:#fff;font-weight:800;font-size:.82em;letter-spacing:-.03em}
.mark b{color:var(--accent)}
.kicker{display:inline-block;color:var(--accent);font-weight:800;font-size:.8125rem;text-transform:uppercase;letter-spacing:.12em}
.btn{display:inline-block;background:var(--accent);color:#04302a;font-weight:800;padding:13px 22px;border-radius:12px;
  box-shadow:0 8px 26px rgba(31,227,194,.18);transition:transform .12s,box-shadow .12s}
.btn:hover{transform:translateY(-1px);box-shadow:0 12px 30px rgba(31,227,194,.28)}
/* nav */
.nav{position:sticky;top:0;z-index:30;background:rgba(14,17,20,.82);backdrop-filter:saturate(1.3) blur(12px);border-bottom:1px solid var(--border)}
.nav-in{max-width:var(--wrap);margin:0 auto;display:flex;align-items:center;justify-content:space-between;padding:13px 22px;position:relative}
.brand{display:flex;align-items:center;gap:9px;font-weight:800;letter-spacing:-.02em}
.burger{display:none;background:transparent;border:0;color:var(--text);font-size:22px;line-height:1;cursor:pointer;padding:4px 8px}
.nav-links{display:flex;align-items:center;gap:18px;font-weight:600;color:var(--muted)}
.nav-links a:hover{color:var(--text)}
.nav .cta{background:var(--accent);color:#04302a;padding:9px 15px;border-radius:10px}
.nav .cta:hover{color:#04302a}
.langsw{display:inline-flex;gap:2px;font-size:13px;font-weight:800}
.langsw a{color:var(--muted);padding:5px 9px;border-radius:8px}
.langsw a:hover{color:var(--text)}
.langsw a.on{color:#04302a;background:var(--accent)}
/* post head + hero */
.wrap{max-width:var(--wrap);margin:0 auto;padding:34px 22px 10px}
.post-head{max-width:860px;margin:0 auto 22px}
.post-head h1{font-size:clamp(2rem,1.4rem + 3vw,3.15rem);line-height:1.08;letter-spacing:-.02em;font-weight:800;margin:12px 0 14px}
.pmeta{display:flex;align-items:center;gap:9px;color:var(--muted);font-size:.9rem;font-weight:600}
.pmeta i{font-style:normal;opacity:.5}
.hero-media{margin:0 0 6px;background:var(--surface2);border:1px solid var(--border);
  border-top:3px solid var(--accent);border-radius:16px;overflow:hidden;box-shadow:0 24px 60px rgba(0,0,0,.45);line-height:0}
.hero-media img{width:100%;height:auto;display:block}
/* layout */
.layout{display:grid;grid-template-columns:minmax(0,var(--content)) var(--side);gap:48px;max-width:var(--wrap);margin:34px auto 0;align-items:start}
.article-main{min-width:0}
.article-body{font-size:1.125rem}
.article-body>*+*{margin-top:1.35em}
.article-body .lead{font-size:1.28rem;line-height:1.55;color:#cfd8dd}
.article-body p{margin:0}
.article-body h2{font-size:clamp(1.5rem,1.2rem + 1.2vw,2rem);line-height:1.18;letter-spacing:-.01em;font-weight:800;
  margin-top:2.4em;scroll-margin-top:96px}
.article-body a{color:var(--accent);text-decoration:underline;text-underline-offset:3px}
.article-body a:hover{color:var(--accent2)}
.article-body .btn{color:#04302a;text-decoration:none}   /* buttons keep dark text — not the teal in-body link colour */
.article-body .btn:hover{color:#04302a}
.article-figure{margin:2em 0;line-height:0}
.article-figure img{width:100%;height:auto;display:block;background:var(--surface2);
  border:1px solid var(--border);border-radius:14px}
.article-body table{width:100%;border-collapse:collapse;margin:1.8em 0;font-size:.94rem;display:block;overflow-x:auto;white-space:nowrap}
.article-body th,.article-body td{border:1px solid var(--border);padding:9px 13px;text-align:left;white-space:normal}
.article-body thead th{background:var(--surface2);font-weight:800;color:var(--text)}
.article-body tbody tr:nth-child(even){background:rgba(255,255,255,.02)}
.article-body td{color:#cdd6db}
.article-body ul,.article-body ol{margin:1.1em 0;padding-left:22px}
.article-body li{margin:6px 0}
.article-body li::marker{color:var(--accent)}
.article-body h2 + p,.article-body h2 + ul,.article-body h2 + table{margin-top:.9em}
.tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:30px;border-top:1px solid var(--border);padding-top:20px}
.tag{color:var(--muted);font-size:.9rem;font-weight:600}
/* cards / sidebar */
.card{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:18px}
.card-h{font-size:.75rem;text-transform:uppercase;letter-spacing:.1em;color:var(--muted);font-weight:800;margin-bottom:12px}
.sidebar{position:sticky;top:88px;align-self:start;max-height:calc(100vh - 104px);overflow-y:auto;
  display:flex;flex-direction:column;gap:18px;scrollbar-width:thin}
.toc{list-style:none;margin:0;padding:0;counter-reset:toc}
.toc li{margin:0}
.toc a{display:block;padding:7px 10px 7px 14px;border-left:2px solid transparent;color:var(--muted);
  font-size:.9375rem;line-height:1.4;border-radius:0 8px 8px 0;transition:color .12s,border-color .12s,background .12s}
.toc a:hover{color:var(--text);background:rgba(255,255,255,.03)}
.toc a.is-active{color:var(--accent);border-left-color:var(--accent);background:rgba(31,227,194,.06);font-weight:700}
.toc-mobile{display:none}
/* cta card */
.ctacard{background:linear-gradient(150deg,#122a2b,#0f1a20);border:1px solid var(--border);border-radius:16px;padding:20px}
.ctacard h3{margin:0 0 7px;font-size:1.18rem;letter-spacing:-.01em}
.ctacard p{margin:0 0 14px;color:var(--muted);font-size:.95rem;line-height:1.5}
.ctacard.inline{margin:2.2em 0;padding:24px}
.ctacard .btn{width:100%;text-align:center}
/* video + subscribe */
.vcard .video-facade{position:relative;display:block;width:100%;aspect-ratio:16/9;border:0;padding:0;cursor:pointer;
  background-size:cover;background-position:center;border-radius:10px;overflow:hidden}
.vcard .playbtn{position:absolute;inset:0;margin:auto;width:54px;height:54px;display:flex;align-items:center;justify-content:center;
  background:rgba(31,227,194,.92);color:#04302a;border-radius:50%;font-size:20px;box-shadow:0 8px 24px rgba(0,0,0,.4)}
.video-iframe{width:100%;aspect-ratio:16/9;border:0;border-radius:10px;display:block}
.subcard{display:flex;align-items:center;gap:12px}
.subcard .subtext{flex:1;min-width:0}
.subname{font-weight:800}
.submeta{color:var(--muted);font-size:.82rem}
.subbtn{background:#ff2f42;color:#fff;font-weight:800;font-size:.85rem;padding:8px 14px;border-radius:999px;white-space:nowrap}
/* read next */
.readnext .rn{display:block;padding:11px 0;border-top:1px solid var(--border);font-weight:700;font-size:.98rem;line-height:1.3}
.readnext .rn:first-of-type{border-top:0}
.readnext .rn span{display:block;color:var(--accent);font-size:.7rem;text-transform:uppercase;letter-spacing:.08em;margin-bottom:3px;font-weight:800}
.readnext .rn:hover{color:var(--accent)}
/* key takeaways (TL;DR) + FAQ — AEO */
.tldr{background:linear-gradient(150deg,#12241f,#101a1d);border:1px solid var(--border);border-left:3px solid var(--accent);
  border-radius:14px;padding:16px 20px;margin:1.8em 0}
.tldr-h{font-size:.72rem;text-transform:uppercase;letter-spacing:.11em;color:var(--accent);font-weight:800;margin-bottom:9px}
.tldr ul{margin:0;padding-left:20px}
.tldr li{margin:6px 0;color:#dbe3e7;font-size:1rem;line-height:1.5}
.faq{margin-top:2.6em;border-top:1px solid var(--border);padding-top:6px}
.faq h2{margin-top:1em;scroll-margin-top:96px}
.faq-item{padding:16px 0;border-bottom:1px solid var(--border)}
.faq-item h3{font-size:1.12rem;font-weight:700;line-height:1.3;margin:0 0 7px;color:var(--text)}
.faq-item p{margin:0;color:var(--muted);line-height:1.6;font-size:1.02rem}
/* index */
.idxhero{max-width:760px;margin:66px auto 30px;padding:0 22px;text-align:center}
.idxhero h1{font-size:clamp(2.4rem,1.6rem + 4vw,3.8rem);line-height:1.03;letter-spacing:-.03em;font-weight:800;margin:12px 0 14px}
.idxhero p{font-size:1.16rem;color:var(--muted);margin:0 auto 24px;max-width:600px}
.grid{max-width:var(--wrap);margin:14px auto 80px;padding:0 22px;display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:24px}
.pcard{display:flex;flex-direction:column;background:var(--surface);border:1px solid var(--border);border-radius:16px;overflow:hidden;
  transition:transform .14s,border-color .14s,box-shadow .14s}
.pcard:hover{transform:translateY(-3px);border-color:#3a4652;box-shadow:0 18px 44px rgba(0,0,0,.4)}
.pcard-img{background:var(--surface2);border-bottom:1px solid var(--border);line-height:0}
.pcard-img img{width:100%;height:auto;display:block}
.pcard-body{padding:16px 18px 20px}
.pcard h2{font-size:1.22rem;line-height:1.22;letter-spacing:-.01em;margin:8px 0 8px;font-weight:800}
.pcard p{color:var(--muted);font-size:.93rem;margin:0 0 12px}
.pcard .more{color:var(--accent);font-weight:700;font-size:.86rem}
/* footer */
.foot{border-top:1px solid var(--border);margin-top:40px;background:rgba(0,0,0,.15)}
.foot-in{max-width:var(--wrap);margin:0 auto;padding:34px 22px 60px;text-align:center;color:var(--muted)}
.foot-brand{display:flex;align-items:center;justify-content:center;gap:8px;font-weight:800;color:var(--text);margin-bottom:8px}
.foot p{margin:6px 0}
.foot .muted{font-size:.82rem}
.foot a{color:var(--accent);font-weight:600}
/* responsive */
@media(max-width:1079px){
  .layout{grid-template-columns:1fr;gap:30px}
  .toc-desktop{display:none}
  .toc-mobile{display:block;background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:8px 14px;margin-bottom:6px}
  .toc-mobile summary{cursor:pointer;font-weight:800;font-size:.8rem;text-transform:uppercase;letter-spacing:.09em;color:var(--muted);padding:8px 0;list-style:none}
  .toc-mobile summary::-webkit-details-marker{display:none}
  .toc-mobile summary::after{content:"⌄";float:right;font-size:1.1rem;line-height:1}
  .toc-mobile[open] summary::after{content:"⌃"}
  .toc-mobile .toc{columns:2;padding:6px 0 10px}
  .sidebar{position:static;max-height:none;overflow:visible;margin-top:8px}
}
@media(max-width:720px){
  .wrap{padding:24px 18px 6px}
  .layout{margin-top:24px}
  .hero-media{border-radius:12px}
  .article-body{font-size:1.06rem}
  .toc-mobile .toc{columns:1}
  .grid{grid-template-columns:1fr;gap:18px}
}
@media(max-width:760px){
  .brandtext{display:none}                 /* hide the wordmark on mobile — keep the JH mark */
  .burger{display:block}
  .nav-links{position:absolute;top:calc(100% + 6px);right:12px;left:12px;flex-direction:column;align-items:stretch;
    gap:4px;background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:10px;
    box-shadow:0 20px 50px rgba(0,0,0,.55);display:none;z-index:40}
  .nav-links.open{display:flex}
  .nav-links a{padding:11px 12px;border-radius:8px}
  .nav-links .cta{text-align:center;margin-top:4px}
  .nav-links .langsw{padding:6px 4px}
}
@media(prefers-reduced-motion:reduce){ html{scroll-behavior:auto} .btn:hover,.pcard:hover{transform:none} }