:root{
  --blue:#1f4e79; --blue-dark:#163a5a; --ink:#1a2330; --body:#33414f; --muted:#667085;
  --line:#e3e8ee; --bg:#ffffff; --bg-soft:#f5f8fb; --bg-tint:#eef4fa; --gold:#c08a2d;
  --ok:#1d7a52; --radius:12px; --maxw:1120px; --narrow:740px;
  --shadow:0 1px 2px rgba(16,24,40,.06),0 8px 24px rgba(16,24,40,.06);
  --font:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font-family:var(--font);color:var(--body);background:var(--bg);line-height:1.65;font-size:17px}
h1,h2,h3,h4{color:var(--ink);line-height:1.25;font-weight:700;margin:1.6em 0 .5em}
h1{font-size:2.1rem;margin-top:.2em;letter-spacing:-.01em}
h2{font-size:1.5rem;margin-top:1.8em}
h3{font-size:1.2rem}
p{margin:0 0 1.05em}
a{color:var(--blue);text-underline-offset:2px}
a:hover{color:var(--blue-dark)}
img{max-width:100%;height:auto}
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 20px}
.container--narrow{max-width:var(--narrow)}
.muted{color:var(--muted)}
.small{font-size:.85rem}
.eyebrow{text-transform:uppercase;letter-spacing:.08em;font-size:.78rem;font-weight:700;color:var(--blue);margin:0 0 .4em}
.lede{font-size:1.2rem;color:var(--ink);margin:0 0 1.2em}
.byline{font-size:.9rem;color:var(--muted);border-bottom:1px solid var(--line);padding-bottom:1em;margin-bottom:1.4em}
.skip-link{position:absolute;left:-999px}
.skip-link:focus{left:8px;top:8px;background:#fff;padding:8px 12px;border:2px solid var(--blue);border-radius:8px;z-index:100}

/* header */
.site-header{border-bottom:1px solid var(--line);position:sticky;top:0;background:rgba(255,255,255,.92);backdrop-filter:saturate(180%) blur(8px);z-index:50}
.site-header__inner{display:flex;align-items:center;justify-content:space-between;min-height:64px}
.brand{display:flex;align-items:center;gap:.5rem;font-weight:800;color:var(--ink);text-decoration:none;font-size:1.08rem}
.brand__mark{color:var(--blue);font-size:1.3rem}
.brand--footer{color:#fff}
.nav__toggle{display:none;background:var(--bg-soft);border:1px solid var(--line);border-radius:8px;padding:.45rem .7rem;font-weight:600;color:var(--ink)}
.nav__menu{display:flex;gap:1.25rem;list-style:none;margin:0;padding:0}
.nav__menu a{color:var(--body);text-decoration:none;font-weight:600;font-size:.95rem;padding:.4rem 0;border-bottom:2px solid transparent}
.nav__menu a:hover,.nav__menu a[aria-current=page]{color:var(--blue);border-color:var(--blue)}

/* hero */
.hero{background:linear-gradient(180deg,var(--bg-tint),#fff);border-bottom:1px solid var(--line)}
.hero__inner{padding:64px 0 52px;max-width:820px}
.hero h1{font-size:2.6rem;margin:.1em 0 .3em}
.hero .lede{font-size:1.3rem;max-width:680px}
.badge-row{display:flex;flex-wrap:wrap;gap:.6rem;margin:1.2em 0 0}
.badge{display:inline-flex;align-items:center;gap:.4rem;background:#fff;border:1px solid var(--line);border-radius:999px;padding:.4rem .85rem;font-size:.85rem;font-weight:600;color:var(--ink);box-shadow:var(--shadow)}
.badge::before{content:"\2713";color:var(--ok);font-weight:800}

/* buttons */
.btn{display:inline-block;background:var(--blue);color:#fff;text-decoration:none;font-weight:700;padding:.8rem 1.4rem;border-radius:10px;border:1px solid var(--blue);cursor:pointer;font-size:1rem}
.btn:hover{background:var(--blue-dark);color:#fff}
.btn--ghost{background:#fff;color:var(--blue)}
.btn--ghost:hover{background:var(--bg-soft);color:var(--blue-dark)}
.btn-row{display:flex;flex-wrap:wrap;gap:.8rem;margin:1.6em 0 0}

/* sections */
.section{padding:54px 0}
.section--soft{background:var(--bg-soft);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.section__head{max-width:680px;margin-bottom:1.6em}
.section__head h2{margin-top:0}

/* cards */
.grid{display:grid;gap:20px}
.grid--3{grid-template-columns:repeat(3,1fr)}
.grid--2{grid-template-columns:repeat(2,1fr)}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow);display:flex;flex-direction:column}
.card h3{margin:.1em 0 .35em}
.card p{color:var(--body);margin-bottom:1em}
.card a.card__link{margin-top:auto;font-weight:700;text-decoration:none}
.card a.card__link::after{content:" \2192"}
.card__icon{width:40px;height:40px;border-radius:10px;background:var(--bg-tint);color:var(--blue);display:flex;align-items:center;justify-content:center;font-size:1.2rem;font-weight:800;margin-bottom:.6em}

/* prose article */
.prose{padding:42px 0 56px}
.prose ul,.prose ol{margin:0 0 1.1em;padding-left:1.3em}
.prose li{margin:.35em 0}
.prose h2{border-top:1px solid var(--line);padding-top:1.1em}
.prose table{width:100%;border-collapse:collapse;margin:1.2em 0;font-size:.95rem}
.prose th,.prose td{border:1px solid var(--line);padding:.6rem .7rem;text-align:left;vertical-align:top}
.prose th{background:var(--bg-tint);color:var(--ink);font-weight:700}
.prose tr:nth-child(even) td{background:var(--bg-soft)}

/* callouts */
.callout{background:var(--bg-soft);border:1px solid var(--line);border-left:4px solid var(--blue);border-radius:10px;padding:18px 20px;margin:1.4em 0}
.callout--disclaimer{border-left-color:var(--gold);background:#fdf9f1;font-size:.92rem}
.callout--key{border-left-color:var(--ok);background:#f1f9f5}
.callout p:last-child{margin-bottom:0}

/* TOC */
.toc{background:#fff;border:1px solid var(--line);border-radius:10px;padding:16px 20px;margin:0 0 1.6em}
.toc p{font-weight:700;margin:0 0 .4em;color:var(--ink)}
.toc ul{margin:0;padding-left:1.1em}
.toc a{text-decoration:none}

/* calc / quiz */
.tool{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px;box-shadow:var(--shadow);margin:1.4em 0}
.field{margin:0 0 1rem}
.field label{display:block;font-weight:600;color:var(--ink);margin-bottom:.3rem;font-size:.95rem}
.field input,.field select{width:100%;padding:.7rem .8rem;border:1px solid var(--line);border-radius:8px;font-size:1rem;font-family:inherit}
.field .hint{font-size:.82rem;color:var(--muted);margin-top:.25rem}
.result{margin-top:1.2em;padding:20px;border-radius:10px;background:var(--bg-tint);border:1px solid var(--line)}
.result .big{font-size:2.2rem;font-weight:800;color:var(--blue);line-height:1}
.two-col{display:grid;grid-template-columns:1fr 1fr;gap:1rem}

/* email capture */
.capture{background:var(--blue);color:#fff;border-radius:var(--radius);padding:30px;margin:1.8em 0}
.capture h3{color:#fff;margin-top:0}
.capture p{color:#dce7f2}
.capture form{display:flex;gap:.6rem;flex-wrap:wrap;margin-top:1em}
.capture input{flex:1;min-width:220px;padding:.75rem .9rem;border-radius:8px;border:1px solid #2f5d86;font-size:1rem}
.capture .btn{background:#fff;color:var(--blue);border-color:#fff}

/* footer */
.site-footer{background:var(--ink);color:#c4cdd8;margin-top:40px;padding:42px 0 28px}
.site-footer__grid{display:grid;grid-template-columns:1.4fr 1fr;gap:28px;padding-bottom:22px;border-bottom:1px solid #2c3848}
.site-footer .muted{color:#9aa7b5}
.footer-links{list-style:none;margin:0;padding:0;columns:2;gap:1rem}
.footer-links a{color:#c4cdd8;text-decoration:none;display:block;padding:.25rem 0;font-size:.92rem}
.footer-links a:hover{color:#fff}
.disclaimer-footer{margin-top:18px;max-width:none}

@media(max-width:840px){
  .grid--3{grid-template-columns:1fr}
  .grid--2{grid-template-columns:1fr}
  .site-footer__grid{grid-template-columns:1fr}
  .hero h1{font-size:2rem}
  .hero .lede{font-size:1.15rem}
  .nav__toggle{display:block}
  .nav__menu{position:absolute;left:0;right:0;top:64px;background:#fff;border-bottom:1px solid var(--line);flex-direction:column;gap:0;padding:8px 20px;display:none;box-shadow:var(--shadow)}
  .nav__menu.is-open{display:flex}
  .nav__menu li{border-bottom:1px solid var(--line)}
  .nav__menu li:last-child{border-bottom:0}
  .nav__menu a{display:block;padding:.8rem 0}
  .two-col{grid-template-columns:1fr}
}

.diagram{margin:1.5rem 0;}
.diagram figcaption{margin-top:.4rem;text-align:center;}

.breadcrumb{font-size:.82rem;color:#6b7785;margin:0 0 1rem;}
.breadcrumb a{color:#6b7785;text-decoration:none;}
.breadcrumb a:hover{text-decoration:underline;}
.breadcrumb__cur{color:#33404d;}