/* Palette: brand navy #194058 and brand blue #3c9fdd (1xPartners), green for download CTAs. */
:root{
  --navy:#194058;--navy-2:#0f2c40;--blue:#3c9fdd;--blue-soft:#e8f3fb;
  --green:#3fa34d;--green-2:#338a3f;
  --bg:#f3f6f9;--fg:#14212d;--muted:#5d6e7e;--card:#fff;--line:#dce4ec;
  --radius:14px;--shadow:0 1px 2px rgba(16,40,60,.06),0 4px 16px rgba(16,40,60,.06);
}
@media (prefers-color-scheme:dark){:root{
  --bg:#0c1822;--fg:#e4edf4;--muted:#93a6b6;--card:#132634;--line:#22394a;--blue-soft:#163447;
  --shadow:0 1px 2px rgba(0,0,0,.3)}}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.65 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;padding-bottom:84px}
.wrap{max-width:860px;margin:0 auto;padding:0 16px}
a{color:var(--blue)}
img,svg{max-width:100%}

/* header */
.top{background:var(--navy);color:#fff;position:sticky;top:0;z-index:20}
.bar{display:flex;align-items:center;justify-content:space-between;height:56px}
.logo{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none;font-weight:700;font-size:18px;letter-spacing:.2px}
.mark{width:30px;height:30px}
.age{border:2px solid rgba(255,255,255,.85);border-radius:999px;padding:1px 8px;font-size:12px;font-weight:700}
.tabs{display:flex;gap:4px;overflow-x:auto;padding-bottom:10px;scrollbar-width:none}
.tabs::-webkit-scrollbar{display:none}
.tabs a{color:#c9dbe8;text-decoration:none;font-size:14px;white-space:nowrap;padding:6px 12px;border-radius:999px}
.tabs a:hover{background:rgba(255,255,255,.08);color:#fff}
.tabs a[aria-current]{background:var(--blue);color:#fff;font-weight:600}

/* hero */
.hero{background:linear-gradient(180deg,var(--navy) 0%,var(--navy-2) 100%);color:#fff;padding:28px 0 32px}
.hero h1{font-size:clamp(26px,5.4vw,40px);line-height:1.15;margin:0 0 12px;letter-spacing:-.3px}
.hero .lead{font-size:17px;color:#d3e2ee;margin:0 0 16px;max-width:680px}
.hero .meta{color:#8fb0c8;font-size:13px;margin:14px 0 0}
.chips{list-style:none;display:flex;flex-wrap:wrap;gap:8px;padding:0;margin:0 0 20px}
.chips li{font-size:13px;font-weight:600;padding:5px 12px;border-radius:999px;background:rgba(60,159,221,.18);color:#bfe1f7;border:1px solid rgba(60,159,221,.35)}
.chips li::before{content:"✓ ";color:#7fd08a}
.hero-cta{display:flex;flex-wrap:wrap;gap:12px;align-items:stretch}
.hero .promo{background:rgba(255,255,255,.06);border:1.5px dashed rgba(255,255,255,.35);color:#fff;flex:1 1 260px}
.hero .promo-label{color:#9fc0d6}

/* promo + buttons */
.promo{display:flex;align-items:center;gap:10px;padding:10px 12px;border-radius:var(--radius);border:1.5px dashed var(--blue);background:var(--card)}
.promo-label{font-size:13px;text-transform:uppercase;letter-spacing:.6px;color:var(--muted)}
.promo code{font:700 20px/1 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:1px}
.promo button{margin-left:auto;padding:9px 14px;border:0;border-radius:10px;background:var(--blue);color:#fff;font-weight:700;cursor:pointer;min-width:44px}
.promo button:active{transform:scale(.97)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:14px 22px;border-radius:var(--radius);background:var(--green);color:#fff;font-weight:700;text-decoration:none;text-align:center;flex:1 1 220px;box-shadow:0 4px 14px rgba(63,163,77,.35);transition:background .15s,transform .1s}
.btn:hover{background:var(--green-2)}
.btn:active{transform:translateY(1px)}
.btn.alt{background:var(--blue);box-shadow:0 4px 14px rgba(60,159,221,.3)}
.btn.big{font-size:17px;padding:16px 24px}
.ico{width:20px;height:20px}
.cta{display:flex;flex-wrap:wrap;gap:12px;margin:24px 0}

/* content */
main{padding-top:8px}
h2{font-size:clamp(20px,3.6vw,25px);line-height:1.25;margin:36px 0 10px;letter-spacing:-.2px}
h3{font-size:18px;margin:20px 0 6px}
section{scroll-margin-top:110px}
.toc{background:var(--card);border-radius:var(--radius);padding:14px 18px;margin:20px 0;box-shadow:var(--shadow)}
.toc b{font-size:14px;text-transform:uppercase;letter-spacing:.6px;color:var(--muted)}
.toc ol{margin:8px 0 0;padding-left:20px}
.toc a{color:var(--fg);text-decoration:none}
.toc a:hover{color:var(--blue)}
ol>li::marker{color:var(--blue);font-weight:700}
table{width:100%;border-collapse:separate;border-spacing:0;margin:14px 0;font-size:15px;background:var(--card);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
th,td{padding:10px 12px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}
tr:last-child td{border-bottom:0}
th{background:var(--navy);color:#fff;font-weight:600}
.note{padding:12px 14px;border-left:4px solid var(--blue);background:var(--blue-soft);border-radius:0 10px 10px 0;margin:14px 0}
details{background:var(--card);border-radius:12px;padding:12px 16px;margin:8px 0;box-shadow:var(--shadow)}
summary{font-weight:600;cursor:pointer;list-style:none;display:flex;justify-content:space-between;gap:12px}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";color:var(--blue);font-size:20px;line-height:1}
details[open] summary::after{content:"−"}
details p{margin:8px 0 2px;color:var(--muted)}
.related{margin-top:40px}
.related ul{list-style:none;padding:0;display:grid;gap:8px}
.related a{display:block;padding:12px 16px;background:var(--card);border-radius:12px;text-decoration:none;color:var(--fg);font-weight:600;box-shadow:var(--shadow)}
.related a::after{content:" →";color:var(--blue)}

/* sticky mobile CTA */
.sticky{position:fixed;left:0;right:0;bottom:0;padding:10px 16px calc(10px + env(safe-area-inset-bottom));background:var(--navy);display:flex;z-index:30;box-shadow:0 -4px 16px rgba(0,0,0,.15)}
.sticky .btn{flex:1;padding:13px}
@media (min-width:900px){.sticky{display:none}body{padding-bottom:0}}

/* footer */
footer{margin-top:56px;padding:28px 0;background:var(--navy-2);color:#9fb7c9;font-size:14px}
footer a{color:#cfe3f1}
.rg{padding:12px 14px;border-left:4px solid var(--blue);background:rgba(255,255,255,.04);border-radius:0 10px 10px 0;color:#d6e4ee}
.disclosure{font-size:12px;opacity:.8}
.meta{color:var(--muted);font-size:13px}

/* region chooser / 404 */
.regions{list-style:none;padding:0;display:grid;gap:10px;margin:20px 0}
.regions a{display:block;padding:16px;background:var(--card);border-radius:var(--radius);text-decoration:none;font-weight:600;color:var(--fg);box-shadow:var(--shadow)}
.regions a::after{content:" →";color:var(--blue)}

/* side banner columns (official 1xPartners media): static, start under the hero, desktop only */
.page{position:relative}
.rail{display:none;position:absolute;top:24px;bottom:0;overflow:hidden;width:300px}
.rail-left{right:calc(50% + 430px + 24px)}
.rail-right{left:calc(50% + 430px + 24px)}
.slot{display:flex;flex-direction:column;align-items:center;margin-bottom:28px}
.rail iframe{display:none;border:0;border-radius:10px;overflow:hidden;box-shadow:var(--shadow)}
.ad-label{display:block;font-size:11px;letter-spacing:.6px;text-transform:uppercase;color:var(--muted);margin-bottom:6px}
@media (min-width:1220px){.rail{display:block;width:160px}.rail .bn{display:block}}
@media (min-width:1560px){.rail{width:300px}.rail .bn{display:none}.rail .bw{display:block}}

/* answer-first summary block — the short, quotable answer */
.summary{background:rgba(255,255,255,.07);border-left:4px solid var(--blue);border-radius:0 12px 12px 0;padding:12px 16px;margin:0 0 20px;max-width:680px}
.summary b{display:block;font-size:12px;letter-spacing:.7px;text-transform:uppercase;color:#9fc0d6;margin-bottom:4px}
.summary p{margin:0;color:#eaf2f8}