/* ============================================================
   Layerform, shared stylesheet for content / guide pages.
   Lightweight, brand-consistent (ink #0F172A, accent #2563EB,
   Inter). Article-focused typography for fast, readable pages.
   ============================================================ */

:root{
  --ink:#0F172A; --accent:#2563EB; --accent-dark:#1D4ED8;
  --slate-800:#1E293B; --slate-700:#334155; --slate-600:#475569;
  --slate-500:#64748B; --slate-300:#CBD5E1; --slate-200:#E2E8F0;
  --slate-100:#F1F5F9; --slate-50:#F8FAFC;
  --brand-dark:#0B1220; --white:#fff;
  --maxw:46rem; --radius:14px;
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  font-family:'Inter',ui-sans-serif,system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;
  font-feature-settings:'cv11','ss01';
  color:var(--slate-700); background:var(--white); line-height:1.75;
  -webkit-font-smoothing:antialiased; text-rendering:optimizeLegibility;
}
a{color:var(--accent);text-decoration:none}
a:hover{color:var(--accent-dark)}
img,svg{display:block;max-width:100%}
::selection{background:var(--accent);color:#fff}
:focus-visible{outline:3px solid var(--accent);outline-offset:3px;border-radius:4px}
.container{width:100%;max-width:72rem;margin-inline:auto;padding-inline:1.5rem}

/* ---------- Header ---------- */
.site-header{
  position:sticky;top:0;z-index:40;
  background:rgba(255,255,255,.9);
  backdrop-filter:saturate(180%) blur(12px);
  -webkit-backdrop-filter:saturate(180%) blur(12px);
  border-bottom:1px solid var(--slate-200);
}
.site-header .bar{display:flex;align-items:center;justify-content:space-between;height:4rem}
.site-header img{height:1.85rem;width:auto}
.btn{
  display:inline-flex;align-items:center;gap:.5rem;
  font-weight:600;font-size:.95rem;line-height:1;
  padding:.65rem 1.15rem;border-radius:999px;
  background:var(--accent);color:#fff;
  transition:background .2s,transform .2s,box-shadow .2s;
  box-shadow:0 8px 24px rgba(37,99,235,.25);
}
.btn:hover{background:var(--accent-dark);color:#fff;transform:translateY(-1px)}
.btn svg{width:1.05em;height:1.05em}

/* ---------- Article ---------- */
main{padding-block:clamp(2.25rem,5vw,3.75rem)}
article{max-width:var(--maxw);margin-inline:auto}
.crumbs{font-size:.85rem;color:var(--slate-500);margin-bottom:1.4rem}
.crumbs a{color:var(--slate-500)}
.crumbs a:hover{color:var(--accent)}
article h1{
  font-size:clamp(2rem,1.2rem + 2.4vw,2.9rem);line-height:1.12;
  letter-spacing:-.02em;color:var(--ink);font-weight:800;margin:0 0 1rem;
}
.lede{font-size:1.2rem;color:var(--slate-600);margin:0 0 2rem}
article h2{
  font-size:1.55rem;line-height:1.22;letter-spacing:-.01em;
  color:var(--ink);font-weight:700;margin:2.6rem 0 1rem;
}
article h3{font-size:1.18rem;color:var(--ink);font-weight:700;margin:1.8rem 0 .6rem}
article p{margin:0 0 1.15rem}
article ul,article ol{margin:0 0 1.2rem;padding-left:1.3rem}
article li{margin:.45rem 0}
article strong{color:var(--ink);font-weight:600}
.meta-line{font-size:.9rem;color:var(--slate-500);margin:0 0 2rem}

/* ---------- Callout / key points ---------- */
.callout{
  background:var(--slate-50);border:1px solid var(--slate-200);
  border-left:4px solid var(--accent);border-radius:var(--radius);
  padding:1.2rem 1.4rem;margin:2rem 0;
}
.callout strong{display:block;margin-bottom:.4rem;color:var(--ink)}
.callout p:last-child,.callout ul:last-child{margin-bottom:0}

/* ---------- CTA box ---------- */
.cta-box{
  position:relative;overflow:hidden;isolation:isolate;
  background:var(--brand-dark);color:#fff;border-radius:20px;
  padding:clamp(1.75rem,4vw,2.5rem);margin:2.75rem 0;text-align:center;
}
.cta-box::before{
  content:'';position:absolute;inset:0;z-index:-1;
  background:radial-gradient(60% 90% at 50% 0%,rgba(59,130,246,.35),transparent 70%);
}
.cta-box h2{color:#fff;margin:0 0 .6rem;font-size:1.5rem;font-weight:800}
.cta-box p{color:rgba(226,232,240,.88);margin:0 0 1.4rem}

/* ---------- FAQ ---------- */
.faq{margin-top:1rem}
details.qa{
  border:1px solid var(--slate-200);border-radius:12px;
  padding:0 1.2rem;margin:.7rem 0;background:#fff;
  transition:border-color .2s,box-shadow .2s;
}
details.qa[open]{border-color:rgba(37,99,235,.3);box-shadow:0 4px 12px rgba(15,23,42,.06)}
details.qa summary{
  cursor:pointer;list-style:none;display:flex;justify-content:space-between;gap:1rem;
  align-items:center;padding:1.1rem 0;font-weight:600;color:var(--ink);
}
details.qa summary::-webkit-details-marker{display:none}
details.qa summary::after{content:'+';color:var(--accent);font-weight:700;font-size:1.3rem}
details.qa[open] summary::after{content:'\2013'}
details.qa .a{padding:0 0 1.2rem;color:var(--slate-600)}

/* ---------- Related links ---------- */
.related{margin-top:2.5rem;padding-top:1.75rem;border-top:1px solid var(--slate-200)}
.related h2{font-size:1.15rem;margin:0 0 .8rem}
.related ul{list-style:none;margin:0;padding:0}
.related li{margin:.4rem 0}

/* ---------- Footer ---------- */
.site-footer{
  background:var(--brand-dark);color:#94A3B8;
  border-top:1px solid rgba(255,255,255,.06);padding-block:2.5rem;margin-top:3rem;
}
.site-footer .inner{display:flex;flex-direction:column;gap:1rem}
.site-footer img{height:1.4rem;width:auto}
.site-footer a{color:#94A3B8;transition:color .2s}
.site-footer a:hover{color:#fff}
.flinks{display:flex;flex-wrap:wrap;gap:.5rem 1.4rem;font-size:.9rem}
@media(min-width:720px){.site-footer .inner{flex-direction:row;align-items:center;justify-content:space-between}}

@media (prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}