:root{
  --bg:#0b1020;--card:#121a30;--muted:#93a0bb;--text:#eaf0ff;--accent:#7bdcff;--accent-2:#26c6da;
  --success:#26d07c;--warning:#ffd166;--danger:#ff6b6b;--border:#2a3758;--shadow:0 10px 30px rgba(0,0,0,.35);
  --radius:16px;--radius-sm:10px;--maxw:1120px;
  --font:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,Noto Sans,"Helvetica Neue",Arial,"Apple Color Emoji","Segoe UI Emoji"
}
@media (prefers-color-scheme:light){
  :root{--bg:#f7f9ff;--card:#fff;--muted:#4a587a;--text:#0c1533;--accent:#0a84ff;--accent-2:#007aff;--border:#e3e8f5;--shadow:0 10px 22px rgba(2,16,58,.08)}
}
*{box-sizing:border-box}
html,body{height:100%}
html{overflow-x:hidden}
body{
  margin:0;overflow-x:hidden;
  font-family:var(--font);
  background:radial-gradient(1200px 600px at 80% -10%,rgba(38,198,218,.15),transparent),
             radial-gradient(900px 500px at -10% 10%,rgba(122,220,255,.12),transparent),
             var(--bg);
  color:var(--text);line-height:1.65
}
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:24px}
.header{display:grid;gap:16px;padding:28px 24px;margin:24px 0 12px;
  background:linear-gradient(160deg,rgba(123,220,255,.12),rgba(38,198,218,.05));
  border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow)}
.breadcrumb{font-size:14px;color:var(--muted);margin-top: 80px;}
.breadcrumb a{color:var(--muted);text-decoration:none}
.breadcrumb a:hover{color:var(--accent)}
.hero{display:grid;grid-template-columns:1.2fr .8fr;gap:24px;align-items:center}
@media (max-width:900px){.hero{grid-template-columns:1fr}}
.hero h1{margin:0 0 8px;letter-spacing:-.02em;font-weight:800;font-size:clamp(26px,6vw,42px);line-height:1.15}
.hero p.lead{margin:8px 0 0;color:var(--muted);font-size:clamp(15px,1.9vw,18px)}
.hero-visual{background:conic-gradient(from 180deg at 50% 50%,rgba(123,220,255,.15),rgba(38,198,218,.05),transparent 65%);
  border:1px dashed var(--border);border-radius:var(--radius);padding:18px;aspect-ratio:16/10;display:grid;place-items:center;max-width:100%}
.hero-visual svg{width:88%;height:auto;max-width:100%;opacity:.95}
.meta{display:flex;flex-wrap:wrap;gap:12px 20px;margin-top:6px;color:var(--muted);font-size:14px}
.grid{display:grid;grid-template-columns:280px 1fr;gap:24px;margin:18px 0 60px}
@media (max-width:980px){.grid{grid-template-columns:1fr}}
.toc{position:sticky;top:16px;align-self:start;background:var(--card);border:1px solid var(--border);
  border-radius:var(--radius);padding:16px;box-shadow:var(--shadow)}
@media (max-width:720px){.toc{position:static}}
.toc h3{margin:0 0 10px;font-size:16px}
.toc ol{margin:0;padding-left:18px;display:grid;gap:8px;font-size:15px}
.toc a{color:var(--muted);text-decoration:none}
.toc a:hover{color:var(--accent)}
.main{display:grid;gap:18px}
.article{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:clamp(14px,3.8vw,28px);box-shadow:var(--shadow)}
.article h2{margin-top:28px;font-size:clamp(20px,4.8vw,28px);line-height:1.25}
.article h3{margin-top:18px;font-size:18px;color:var(--muted);font-weight:600}
.article p{margin:10px 0}
.callout{border-left:4px solid var(--accent);background:linear-gradient(0deg,rgba(123,220,255,.09),rgba(123,220,255,.09));
  padding:12px 14px;border-radius:var(--radius-sm)}
.kbd,kbd{padding:2px 6px;border:1px solid var(--border);border-bottom-width:3px;border-radius:6px;background:rgba(255,255,255,.04);
  font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,"Liberation Mono",monospace;font-size:.95em}
code,pre{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,"Liberation Mono",monospace;word-wrap:break-word;word-break:break-word}
pre{white-space:pre-wrap;background:#0d1427;border:1px solid var(--border);border-radius:var(--radius-sm);padding:14px;overflow:auto;max-width:100%}
@media (prefers-color-scheme:light){pre{background:#f1f4fb}}
.checklist{margin:10px 0 0;padding-left:22px}
.checklist li{margin:6px 0}
.badge{display:inline-flex;align-items:center;gap:6px;padding:6px 10px;border-radius:999px;border:1px solid var(--border);
  background:linear-gradient(0deg,rgba(255,255,255,.04),rgba(255,255,255,.04));font-size:13px;color:var(--muted)}
.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:16px}
@media (max-width:720px){.grid-2{grid-template-columns:1fr}}
.card{border:1px solid var(--border);background:white;border-radius:var(--radius);padding:16px;margin-bottom: 15px;}
.faq details{border:1px solid var(--border);border-radius:var(--radius);padding:14px 16px;background:var(--card)}
.faq details+details{margin-top:10px}
.faq summary{cursor:pointer;list-style:none;font-weight:600}
.faq summary::-webkit-details-marker{display:none}
.faq summary:after{content:"+";float:right;color:var(--muted)}
details[open] summary:after{content:"–"}
.cta{display:grid;gap:14px;align-items:center;grid-template-columns:1fr auto;border:1px solid var(--border);
  background:linear-gradient(160deg,rgba(123,220,255,.08),rgba(38,198,218,.04));padding:18px;border-radius:var(--radius)}
@media (max-width:700px){.cta{grid-template-columns:1fr}}
.cta a.button{display:inline-block;text-decoration:none;color:#001422;background:linear-gradient(180deg,var(--accent),var(--accent-2));
  padding:12px 18px;border-radius:12px;font-weight:700;border:none;box-shadow:0 8px 18px rgba(10,132,255,.25)}
.cta .mini{font-size:13px;color:var(--muted)}

/* Small-screen tweaks */
@media (max-width:520px){
  .container{padding:16px}
  .meta{gap:8px}
  .badge{font-size:12px}
  .breadcrumb{font-size:13px}
  .toc{padding:12px;border-radius:12px}
  .article{border-radius:14px}
}

/* Print */
@media print{
  .toc,.cta,.breadcrumb,.hero-visual{display:none!important}
  body{background:#fff;color:#111}
  .article{box-shadow:none;border-color:#ddd}
}



.card-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
}

.card-header img {
  width: 100%;
  height: auto;
  border-radius: 6px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.15);
}

.card-header h3 {
  margin: 0;
  font-size: 18px;
}