:root{
  --ground:#F2F5F8; --surface:#FFFFFF; --surface-2:#F8FAFC;
  --ink:#111925; --ink-2:#314054; --muted:#5D6B80;
  --line:#DCE3EB; --line-strong:#C3CEDA;
  --accent:#1C3E6E; --accent-ink:#FFFFFF; --accent-soft:#E7EEF8;
  --money:#186B45; --money-soft:#E4F2EA;
  --flag:#8E5A11; --flag-soft:#FBF0DC;
  --shadow:0 1px 2px rgba(17,25,37,.05), 0 12px 28px rgba(17,25,37,.07);
  --radius:10px; color-scheme:light;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --ground:#0D1219; --surface:#151D27; --surface-2:#1A2431;
    --ink:#E8EDF4; --ink-2:#BCC8D8; --muted:#8E9DB2;
    --line:#26313F; --line-strong:#36455A;
    --accent:#7FA8DF; --accent-ink:#0D1219; --accent-soft:#1B2838;
    --money:#59B98A; --money-soft:#152A21;
    --flag:#D9A459; --flag-soft:#2A2113;
    --shadow:0 1px 2px rgba(0,0,0,.3), 0 12px 28px rgba(0,0,0,.35);
    color-scheme:dark;
  }
}
:root[data-theme="dark"]{
  --ground:#0D1219; --surface:#151D27; --surface-2:#1A2431;
  --ink:#E8EDF4; --ink-2:#BCC8D8; --muted:#8E9DB2;
  --line:#26313F; --line-strong:#36455A;
  --accent:#7FA8DF; --accent-ink:#0D1219; --accent-soft:#1B2838;
  --money:#59B98A; --money-soft:#152A21;
  --flag:#D9A459; --flag-soft:#2A2113;
  --shadow:0 1px 2px rgba(0,0,0,.3), 0 12px 28px rgba(0,0,0,.35);
  color-scheme:dark;
}

*{box-sizing:border-box}
body{margin:0;background:var(--ground);color:var(--ink);
  font-family:"Source Serif 4",Georgia,"Times New Roman",serif;font-size:17px;line-height:1.65;
  -webkit-font-smoothing:antialiased}
h1,h2,h3,h4{font-family:"Archivo","Helvetica Neue",Arial,sans-serif}
.mono,.num{font-family:"IBM Plex Mono",ui-monospace,Menlo,monospace;font-variant-numeric:tabular-nums}
a{color:var(--accent)}
a:focus-visible,button:focus-visible,select:focus-visible,input:focus-visible{
  outline:2px solid var(--accent);outline-offset:2px;border-radius:4px}
.wrap{max-width:1120px;margin:0 auto;padding-inline:20px}
.prose{max-width:68ch}

.topbar{background:var(--surface);border-bottom:1px solid var(--line);
  position:sticky;top:env(safe-area-inset-top, 0px);z-index:20}
.topbar .wrap{display:flex;align-items:center;gap:26px;height:60px}
.brand{display:flex;align-items:center;gap:9px;text-decoration:none;color:var(--ink);
  font-family:"Archivo",sans-serif;font-weight:700;font-size:17px;letter-spacing:-.2px;white-space:nowrap}
.brand-mark{width:24px;height:24px;border-radius:6px;background:var(--accent);color:var(--accent-ink);
  display:grid;place-items:center;font-family:"IBM Plex Mono",monospace;font-size:13px;font-weight:600}
.topnav{display:flex;gap:20px;margin-left:auto;font-family:"Archivo",sans-serif;font-size:14.5px}
.topnav a{color:var(--ink-2);text-decoration:none}
.topnav a:hover{color:var(--accent)}
@media(max-width:720px){.topnav{display:none}}

.crumbs{font-family:"Archivo",sans-serif;font-size:13px;color:var(--muted);padding-block:18px 0}
.crumbs a{color:var(--muted);text-decoration:none}
.crumbs a:hover{text-decoration:underline}
.pagehead{padding-block:14px 24px}
.pagehead h1{font-size:clamp(32px,5vw,46px);line-height:1.08;letter-spacing:-1.1px;font-weight:700;
  margin:6px 0 0;text-wrap:balance}
.standfirst{font-size:19px;color:var(--ink-2);margin:14px 0 0;max-width:62ch}
.stamp{display:inline-flex;align-items:center;gap:8px;margin-top:16px;
  font-family:"IBM Plex Mono",monospace;font-size:12.5px;color:var(--muted);
  background:var(--surface);border:1px solid var(--line);padding:5px 11px;border-radius:999px}

.alert{display:flex;gap:14px;align-items:flex-start;background:var(--flag-soft);
  border:1px solid color-mix(in srgb,var(--flag) 32%,transparent);border-radius:var(--radius);
  padding:16px 18px;margin-bottom:24px}
.alert .ic{flex:0 0 auto;width:22px;height:22px;border-radius:999px;background:var(--flag);
  color:var(--flag-soft);display:grid;place-items:center;font-family:"Archivo",sans-serif;
  font-weight:700;font-size:14px;margin-top:2px}
.alert p{margin:0;font-size:16px;color:var(--ink-2)}
.alert strong{color:var(--ink)}

.tool{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:22px;align-items:start}
@media(max-width:900px){.tool{grid-template-columns:minmax(0,1fr)}}
.panel{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}
.panel-hd{padding:15px 22px;border-bottom:1px solid var(--line);font-family:"Archivo",sans-serif;
  font-weight:600;font-size:14px;letter-spacing:.7px;text-transform:uppercase;color:var(--muted)}
.panel-bd{padding:22px}
.fields{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
.f-full{grid-column:1/-1}
.lab{display:block;font-family:"Archivo",sans-serif;font-size:13px;font-weight:600;color:var(--ink-2);margin-bottom:6px}
.hint{font-family:"Archivo",sans-serif;font-size:12px;color:var(--muted);margin-top:5px;line-height:1.45}
input[type=number],select{width:100%;height:44px;padding:0 12px;background:var(--surface-2);color:var(--ink);
  border:1px solid var(--line-strong);border-radius:8px;font-family:"IBM Plex Mono",monospace;font-size:15px}
select{font-family:"Archivo",sans-serif;font-size:14.5px;cursor:pointer}
.money-in{position:relative}
.money-in span{position:absolute;left:12px;top:50%;transform:translateY(-50%);color:var(--muted);
  font-family:"IBM Plex Mono",monospace;font-size:15px;pointer-events:none}
.money-in input{padding-left:26px}
.seg{display:flex;background:var(--surface-2);border:1px solid var(--line-strong);border-radius:8px;padding:3px;gap:3px}
.seg button{flex:1;height:36px;border:0;border-radius:6px;background:transparent;cursor:pointer;
  font-family:"Archivo",sans-serif;font-size:14px;font-weight:600;color:var(--muted)}
.seg button[aria-pressed=true]{background:var(--accent);color:var(--accent-ink)}

.stub-hd{padding:15px 22px;border-bottom:1px solid var(--line);display:flex;align-items:baseline;
  justify-content:space-between;gap:12px;flex-wrap:wrap}
.stub-title{font-family:"Archivo",sans-serif;font-weight:700;font-size:16px;letter-spacing:-.2px}
.stub-sub{font-family:"IBM Plex Mono",monospace;font-size:12px;color:var(--muted)}
.stub table{width:100%;border-collapse:collapse}
.stub th{font-family:"Archivo",sans-serif;font-size:11px;font-weight:600;letter-spacing:.7px;
  text-transform:uppercase;color:var(--muted);text-align:right;padding:14px 22px 8px}
.stub th:first-child{text-align:left}
.stub td{padding:8px 22px;border-top:1px solid var(--line);font-family:"IBM Plex Mono",monospace;
  font-size:14.5px;text-align:right;font-variant-numeric:tabular-nums}
.stub td:first-child{text-align:left;font-family:"Archivo",sans-serif;font-size:14px;color:var(--ink-2)}
.stub tr.group td{border-top:1px solid var(--line-strong);background:var(--surface-2);
  font-family:"Archivo",sans-serif;font-size:11px;font-weight:600;letter-spacing:.7px;
  text-transform:uppercase;color:var(--muted);padding-block:9px}
.stub td.sub{padding-left:34px;color:var(--muted)}
.stub tr.gross td{font-weight:600;color:var(--ink)}
.stub tr.ga td{background:var(--accent-soft)}
.stub tr.ga td:first-child{color:var(--accent);font-weight:600}
.netbox{padding:18px 22px;border-top:2px solid var(--ink);background:var(--money-soft);
  display:flex;align-items:flex-end;justify-content:space-between;gap:14px;flex-wrap:wrap}
.netbox .lbl{font-family:"Archivo",sans-serif;font-weight:700;font-size:13px;letter-spacing:.8px;
  text-transform:uppercase;color:var(--money)}
.netbox .big{font-family:"IBM Plex Mono",monospace;font-size:32px;font-weight:600;color:var(--money);
  line-height:1;font-variant-numeric:tabular-nums}
.netbox .yr{font-family:"IBM Plex Mono",monospace;font-size:13px;color:var(--muted);margin-top:5px}
.rate-strip{display:flex;border-top:1px solid var(--line)}
.rate-strip > div{flex:1;padding:12px 22px;border-right:1px solid var(--line)}
.rate-strip > div:last-child{border-right:0}
.rate-strip .k{font-family:"Archivo",sans-serif;font-size:11px;letter-spacing:.7px;text-transform:uppercase;color:var(--muted)}
.rate-strip .v{font-family:"IBM Plex Mono",monospace;font-size:17px;font-weight:500;margin-top:3px;font-variant-numeric:tabular-nums}
.workings{padding:14px 22px;border-top:1px solid var(--line);background:var(--surface-2);
  font-family:"IBM Plex Mono",monospace;font-size:12.5px;color:var(--muted);line-height:1.8}
.workings b{color:var(--ink-2);font-weight:500}

.sec{padding-block:56px}
.sec-hd{margin-bottom:22px}
.sec-hd h2{font-size:28px;letter-spacing:-.6px;margin:0;font-weight:700;text-wrap:balance}
.sec-hd p{margin:9px 0 0;color:var(--ink-2);max-width:66ch}
.eyebrow{font-family:"IBM Plex Mono",monospace;font-size:12px;letter-spacing:1.3px;
  text-transform:uppercase;color:var(--muted);margin:0 0 10px}

.facts{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  box-shadow:var(--shadow);overflow:hidden}
.facts table{width:100%;border-collapse:collapse}
.facts td{padding:13px 22px;border-top:1px solid var(--line);font-size:16px}
.facts tr:first-child td{border-top:0}
.facts td:first-child{font-family:"Archivo",sans-serif;font-size:14px;color:var(--ink-2);width:52%}
.facts td:last-child{font-family:"IBM Plex Mono",monospace;font-size:15px;text-align:right;font-variant-numeric:tabular-nums}
.facts td .no{color:var(--money);font-weight:600}

.article h2{font-size:27px;letter-spacing:-.6px;margin:44px 0 12px;font-weight:700;text-wrap:balance}
.article h2:first-child{margin-top:0}
.article h3{font-size:19px;margin:28px 0 8px;font-weight:600;letter-spacing:-.2px}
.article p{margin:0 0 16px}
.article ul,.article ol{margin:0 0 16px;padding-left:20px}
.article li{margin-bottom:9px}
.article strong{font-weight:600;color:var(--ink)}
.pull{border-left:3px solid var(--accent);padding:2px 0 2px 18px;margin:22px 0;font-size:19px;color:var(--ink-2)}
.tbl-wrap{overflow-x:auto;margin:20px 0;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface)}
table.data{width:100%;border-collapse:collapse;min-width:420px}
table.data th{font-family:"Archivo",sans-serif;font-size:11px;letter-spacing:.7px;text-transform:uppercase;
  color:var(--muted);text-align:left;padding:12px 16px;border-bottom:1px solid var(--line-strong)}
table.data td{padding:10px 16px;border-top:1px solid var(--line);font-size:15px}
table.data td.n,table.data th.n{text-align:right}
table.data td.n{font-family:"IBM Plex Mono",monospace;font-variant-numeric:tabular-nums}

.method{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:26px;box-shadow:var(--shadow)}
.method h3{margin-top:22px}
.method h3:first-of-type{margin-top:0}
.srcs{list-style:none;padding:0;margin:10px 0 0;font-family:"Archivo",sans-serif;font-size:14.5px}
.srcs li{padding:7px 0;border-top:1px solid var(--line)}
.srcs li:first-child{border-top:0}

.cluster{display:grid;grid-template-columns:repeat(auto-fill,minmax(248px,1fr));gap:10px}
.cluster a{display:block;padding:15px 17px;background:var(--surface);border:1px solid var(--line);
  border-radius:8px;text-decoration:none}
.cluster a:hover{border-color:var(--accent);background:var(--accent-soft)}
.cluster .t{font-family:"Archivo",sans-serif;font-weight:600;font-size:15.5px;color:var(--ink)}
.cluster .d{font-family:"Archivo",sans-serif;font-size:13px;color:var(--muted);margin-top:3px;line-height:1.45}

.nearby{display:flex;gap:8px;flex-wrap:wrap}
.nearby a{display:inline-flex;align-items:center;gap:9px;padding:9px 14px;background:var(--surface);
  border:1px solid var(--line);border-radius:999px;text-decoration:none;color:var(--ink);
  font-family:"Archivo",sans-serif;font-size:14.5px}
.nearby a:hover{border-color:var(--accent);background:var(--accent-soft)}
.nearby .r{font-family:"IBM Plex Mono",monospace;font-size:12.5px;color:var(--muted)}

.faq{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:26px 44px}
@media(max-width:760px){.faq{grid-template-columns:minmax(0,1fr)}}
.faq h3{font-family:"Archivo",sans-serif;font-size:17px;font-weight:600;margin:0 0 6px}
.faq p{margin:0;color:var(--ink-2);font-size:16px}

footer.site{background:var(--surface);border-top:1px solid var(--line);margin-top:20px;padding-block:40px}
.foot{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:26px}
@media(max-width:760px){.foot{grid-template-columns:repeat(2,minmax(0,1fr))}}
.foot h4{font-family:"Archivo",sans-serif;font-size:12px;letter-spacing:.8px;text-transform:uppercase;color:var(--muted);margin:0 0 10px}
.foot a{display:block;font-family:"Archivo",sans-serif;font-size:14.5px;color:var(--ink-2);text-decoration:none;padding:3px 0}
.foot a:hover{color:var(--accent)}
.disclaim{margin-top:28px;padding-top:18px;border-top:1px solid var(--line);
  font-family:"Archivo",sans-serif;font-size:13px;color:var(--muted);max-width:80ch}
@media (prefers-reduced-motion: reduce){*{animation:none!important;transition:none!important}}

/* ---- generated-site additions ---- */
.dirsec{padding-block:44px}
.dir-h{font-size:22px!important;letter-spacing:-.4px}
.dir-cur{display:flex;align-items:center;justify-content:space-between;gap:8px;padding:10px 13px;
  background:var(--accent-soft);border:1px solid var(--accent);border-radius:8px;
  font-family:"Archivo",sans-serif;font-size:14.5px;font-weight:600;color:var(--accent)}
.dir-cur em{font-style:normal}
.stategrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(186px,1fr));gap:8px}
.stategrid a{display:flex;align-items:center;justify-content:space-between;gap:8px;padding:10px 13px;
  background:var(--surface);border:1px solid var(--line);border-radius:8px;text-decoration:none;
  color:var(--ink);font-family:"Archivo",sans-serif;font-size:14.5px}
.stategrid a:hover{border-color:var(--accent);background:var(--accent-soft)}
.tag{font-family:"IBM Plex Mono",monospace;font-size:10.5px;letter-spacing:.4px;padding:2px 6px;
  border-radius:4px;white-space:nowrap}
.tag.none{background:var(--money-soft);color:var(--money)}
.tag.flat{background:var(--accent-soft);color:var(--accent)}
.tag.grad{background:var(--surface-2);color:var(--muted);border:1px solid var(--line)}
.fp{font-family:"Archivo",sans-serif;font-size:14px;color:var(--muted);margin:10px 0 0;max-width:34ch}
table.data caption{caption-side:top;text-align:left;padding:12px 16px;font-family:"Archivo",sans-serif;
  font-size:13px;color:var(--muted)}
.facts td .no{color:var(--money);font-weight:600}
.article ol{margin:0 0 16px;padding-left:20px}
.facts td .pend{color:var(--flag);font-weight:600}

/* ---- author byline ---- */
.byline{display:flex;align-items:center;gap:12px;margin-top:18px}
.byline .avatar{width:44px;height:44px;border-radius:999px;object-fit:cover;
  border:1px solid var(--line);flex:0 0 auto;display:block}
.by-txt{display:flex;flex-direction:column;gap:1px;font-family:"Archivo",sans-serif;line-height:1.35}
.by-name{font-size:14.5px;font-weight:600;color:var(--ink)}
.by-name a{color:var(--ink);text-decoration:none;border-bottom:1px solid var(--line-strong)}
.by-name a:hover{color:var(--accent);border-bottom-color:var(--accent)}
.by-meta{font-size:13px;color:var(--muted)}

/* ---- about page ---- */
.abouthead{display:flex;gap:26px;align-items:flex-start}
.abouthead .portrait{width:120px;height:120px;border-radius:999px;object-fit:cover;
  border:1px solid var(--line);box-shadow:var(--shadow);flex:0 0 auto;display:block}
@media(max-width:620px){
  .abouthead{flex-direction:column;gap:16px}
  .abouthead .portrait{width:96px;height:96px}
}

/* ================= HOMEPAGE ================= */
:root{
  --t-pay:#E4F2EA;  --t-pay-ink:#186B45;
  --t-tax:#FBF0DC;  --t-tax-ink:#8E5A11;
  --t-loan:#E7EEF8; --t-loan-ink:#1C3E6E;
  --t-biz:#EFE8F6;  --t-biz-ink:#59357F;
  --t-math:#FDE8EC; --t-math-ink:#96294A;
}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]){
  --t-pay:#152A21;  --t-pay-ink:#6FC79B;
  --t-tax:#2A2113;  --t-tax-ink:#E0AE63;
  --t-loan:#1B2838; --t-loan-ink:#8FB4E8;
  --t-biz:#241C31;  --t-biz-ink:#B998DC;
  --t-math:#2E1A21; --t-math-ink:#E48BA4;
}}
:root[data-theme="dark"]{
  --t-pay:#152A21;  --t-pay-ink:#6FC79B;
  --t-tax:#2A2113;  --t-tax-ink:#E0AE63;
  --t-loan:#1B2838; --t-loan-ink:#8FB4E8;
  --t-biz:#241C31;  --t-biz-ink:#B998DC;
  --t-math:#2E1A21; --t-math-ink:#E48BA4;
}

.hero{padding-block:56px 44px;display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,.85fr);
  gap:48px;align-items:center}
@media(max-width:880px){.hero{grid-template-columns:minmax(0,1fr);gap:32px}}
.hero h1{font-size:clamp(36px,5.6vw,56px);line-height:1.04;letter-spacing:-1.6px;font-weight:700;
  margin:10px 0 0;text-wrap:balance}
.hero .sub{font-size:19px;line-height:1.6;color:var(--ink-2);margin:18px 0 0;max-width:52ch}
.ticks{display:flex;gap:18px;flex-wrap:wrap;margin-top:20px;font-family:"Archivo",sans-serif;
  font-size:14px;color:var(--ink-2)}
.ticks span{display:inline-flex;align-items:center;gap:7px}
.ticks svg{flex:0 0 auto}

.finder{margin-top:26px;max-width:560px}
.finder-in{display:flex;align-items:center;gap:11px;height:58px;padding:0 18px;background:var(--surface);
  border:1px solid var(--line-strong);border-radius:999px;box-shadow:var(--shadow)}
.finder-in input{flex-grow:1;height:100%;border:0;outline:0;background:transparent;color:var(--ink);
  font-family:"Archivo",sans-serif;font-size:16px}
.results{margin-top:10px;background:var(--surface);border:1px solid var(--line);border-radius:12px;
  overflow:hidden;box-shadow:var(--shadow)}
.results a{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:10px 16px;
  border-top:1px solid var(--line);text-decoration:none;color:var(--ink);
  font-family:"Archivo",sans-serif;font-size:14.5px}
.results a:first-child{border-top:0}
.results a:hover{background:var(--accent-soft)}
.results .none{padding:14px 16px;font-family:"Archivo",sans-serif;font-size:14px;color:var(--muted)}

/* playful hero calculator */
.heroart{display:flex;justify-content:center}
.heroart .calc{width:236px;background:var(--surface);border:1px solid var(--line-strong);
  border-radius:22px;padding:16px;box-shadow:0 18px 44px rgba(17,25,37,.12);transform:rotate(-3deg)}
.heroart .screen{background:var(--ink);color:var(--money);border-radius:11px;padding:14px 16px;
  font-family:"IBM Plex Mono",monospace;font-size:26px;text-align:right;letter-spacing:1px;
  font-variant-numeric:tabular-nums}
.heroart .screen small{display:block;font-size:11px;color:var(--muted);letter-spacing:.5px;text-align:right}
.heroart .keys{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-top:14px}
.heroart .k{aspect-ratio:1;border-radius:10px;background:var(--surface-2);border:1px solid var(--line);
  display:grid;place-items:center;font-family:"IBM Plex Mono",monospace;font-size:15px;color:var(--ink-2)}
.heroart .k.op{background:var(--accent-soft);color:var(--accent);border-color:transparent}
.heroart .k.eq{background:var(--accent);color:var(--accent-ink);border-color:transparent}

/* category cards */
.cats{display:grid;grid-template-columns:repeat(auto-fit,minmax(232px,1fr));gap:16px}
.cat{display:block;padding:24px;border-radius:16px;text-decoration:none;border:1px solid transparent;
  position:relative;transition:transform .15s ease}
.cat:hover{transform:translateY(-3px)}
.cat .ic{width:44px;height:44px;border-radius:12px;display:grid;place-items:center;background:var(--surface);
  margin-bottom:14px}
.cat h3{font-family:"Archivo",sans-serif;font-size:18px;font-weight:700;margin:0;color:var(--ink)}
.cat p{font-family:"Archivo",sans-serif;font-size:14px;line-height:1.5;color:var(--ink-2);margin:7px 0 0}
.cat .pill{display:inline-block;margin-top:13px;font-family:"IBM Plex Mono",monospace;font-size:11px;
  letter-spacing:.4px;padding:3px 9px;border-radius:999px;background:var(--surface);}
.cat.soon{opacity:.72}
.cat.soon:hover{transform:none}

.statrow{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:0;background:var(--surface);
  border:1px solid var(--line);border-radius:16px;overflow:hidden;box-shadow:var(--shadow)}
@media(max-width:620px){.statrow{grid-template-columns:minmax(0,1fr)}}
.statrow > div{padding:26px;border-right:1px solid var(--line);text-align:center}
.statrow > div:last-child{border-right:0}
@media(max-width:620px){.statrow > div{border-right:0;border-top:1px solid var(--line)}
  .statrow > div:first-child{border-top:0}}
.statrow .n{font-family:"IBM Plex Mono",monospace;font-size:34px;font-weight:600;color:var(--accent);
  line-height:1;font-variant-numeric:tabular-nums}
.statrow .l{font-family:"Archivo",sans-serif;font-size:14px;color:var(--ink-2);margin-top:9px}

/* expandable knowledge section */
.kn{border:1px solid var(--line);border-radius:16px;background:var(--surface);overflow:hidden;
  box-shadow:var(--shadow)}
.kn details{border-top:1px solid var(--line)}
.kn details:first-of-type{border-top:0}
.kn summary{cursor:pointer;list-style:none;padding:18px 24px;font-family:"Archivo",sans-serif;
  font-weight:600;font-size:16.5px;color:var(--ink);display:flex;align-items:center;gap:12px}
.kn summary::-webkit-details-marker{display:none}
.kn summary::after{content:"+";margin-left:auto;font-family:"IBM Plex Mono",monospace;font-size:19px;
  color:var(--muted);line-height:1}
.kn details[open] summary::after{content:"\2212"}
.kn summary:hover{background:var(--surface-2)}
.kn .body{padding:0 24px 22px;max-width:74ch}
.kn .body p{margin:0 0 14px;font-size:16.5px;line-height:1.65}
.kn .body p:last-child{margin-bottom:0}
.kn .body ul{margin:0 0 14px;padding-left:20px}
.kn .body li{margin-bottom:8px}
.tl{list-style:none;padding:0;margin:0 0 14px}
.tl li{display:flex;gap:16px;padding:7px 0;border-top:1px solid var(--line);align-items:baseline}
.tl li:first-child{border-top:0}
.tl .y{font-family:"IBM Plex Mono",monospace;font-size:13.5px;color:var(--accent);flex:0 0 68px;font-weight:500}

.legal h2{font-size:22px;letter-spacing:-.4px;margin:34px 0 10px;font-weight:700}
.legal h2:first-child{margin-top:0}
.legal p,.legal li{font-size:16.5px;line-height:1.7}
.legal .ph{background:var(--flag-soft);color:var(--flag);padding:1px 6px;border-radius:4px;
  font-family:"IBM Plex Mono",monospace;font-size:14px}

/* shareable figure */
.sharefig{margin:0 0 28px;padding:0}
.sharefig img{width:100%;height:auto;display:block;border-radius:14px;border:1px solid var(--line);
  box-shadow:var(--shadow)}
.sharefig figcaption{font-family:"Archivo",sans-serif;font-size:13.5px;color:var(--muted);margin-top:10px}
.article .tl{margin:18px 0 20px}

/* ===== layout repairs ===== */
.topbar .wrap{gap:20px}

/* category grid: one featured card + a 2x2 of the rest */
.cats{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;align-items:stretch}
.cat{display:flex;flex-direction:column;padding:22px}
.cat.feature{grid-column:span 2;grid-row:span 2;padding:30px;justify-content:center}
.cat.feature h3{font-size:24px}
.cat.feature p{font-size:15.5px;max-width:34ch}
.cat.feature .ic{width:52px;height:52px}
.cat .pill{align-self:flex-start;margin-top:auto;padding-top:0}
.cat h3+p{margin-top:6px}
@media(max-width:980px){
  .cats{grid-template-columns:repeat(2,minmax(0,1fr))}
  .cat.feature{grid-column:span 2;grid-row:span 1}
}
@media(max-width:560px){
  .cats{grid-template-columns:minmax(0,1fr)}
  .cat.feature{grid-column:span 1}
}

/* stat row: compact, full-height dividers */
.statrow > div{padding:22px 18px;display:flex;flex-direction:column;align-items:center;justify-content:center}
.statrow .n{font-size:38px}
.statrow .l{margin-top:6px;font-size:14.5px;text-align:center;max-width:22ch}

/* two-column proof block */
.split{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:40px;align-items:start}
@media(max-width:900px){.split{grid-template-columns:minmax(0,1fr);gap:26px}}
.split .prose p{margin:0 0 14px}
.proof{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:22px;
  box-shadow:var(--shadow)}
.proof-hd{font-family:"IBM Plex Mono",monospace;font-size:12px;letter-spacing:1px;text-transform:uppercase;
  color:var(--muted);margin-bottom:14px}
.proof-row{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:13px 15px;
  border-radius:10px;margin-bottom:9px}
.proof-row .lbl{font-family:"Archivo",sans-serif;font-size:14.5px}
.proof-row .val{font-family:"IBM Plex Mono",monospace;font-size:19px;font-weight:600;font-variant-numeric:tabular-nums}
.proof-row.bad{background:var(--flag-soft);color:var(--flag)}
.proof-row.good{background:var(--money-soft);color:var(--money)}
.proof-note{font-family:"Archivo",sans-serif;font-size:13.5px;line-height:1.55;color:var(--muted);
  margin:14px 0 0}

/* tighter vertical rhythm on the homepage */
.sec{padding-block:46px}
.sec-hd{margin-bottom:20px}
.hero{padding-block:48px 34px}

/* footer balance */
.foot{grid-template-columns:1.5fr 1fr 1.2fr 1fr;gap:30px}
@media(max-width:820px){.foot{grid-template-columns:repeat(2,minmax(0,1fr));gap:26px}}
footer.site{padding-block:38px 30px}
.disclaim{margin-top:24px;padding-top:16px}
.disclaim a{color:var(--ink-2)}

/* featured category card */
.cat.feature{display:flex;flex-direction:column}
.cat.feature h3 a{color:var(--ink);text-decoration:none}
.cat.feature h3 a:hover{text-decoration:underline}
.cat.feature .quick{margin-top:18px;display:flex;flex-wrap:wrap;gap:7px;align-items:center}
.cat.feature .qh{font-family:"IBM Plex Mono",monospace;font-size:11px;letter-spacing:.7px;
  text-transform:uppercase;color:var(--muted);width:100%;margin-bottom:2px}
.cat.feature .quick a{font-family:"Archivo",sans-serif;font-size:13.5px;text-decoration:none;
  background:var(--surface);color:var(--ink-2);padding:6px 12px;border-radius:999px;
  border:1px solid transparent}
.cat.feature .quick a:hover{border-color:currentColor;color:var(--ink)}
.cat.feature .go{margin-top:auto;padding-top:20px;font-family:"Archivo",sans-serif;font-size:15px;
  font-weight:600;text-decoration:none}
.cat.feature .go:hover{text-decoration:underline}

/* stat row: even rows, no wrap */
.statrow .l{max-width:none;white-space:nowrap;margin-top:8px}
.statrow > div{min-height:118px}
@media(max-width:560px){.statrow .l{white-space:normal}}

/* ================= DOCUMENT PAGES ================= */
.docbar{background:var(--surface);border-bottom:1px solid var(--line);padding-block:26px 34px;
  margin-bottom:0}
.docbar .crumbs{padding-block:0 0}
.docbar h1{font-size:clamp(30px,4.2vw,44px);line-height:1.08;letter-spacing:-1.2px;font-weight:700;
  margin:10px 0 0;max-width:20ch;text-wrap:balance}
.docbar .standfirst{font-size:19px;line-height:1.6;color:var(--ink-2);margin:16px 0 0;max-width:60ch}
.docbar .byline{margin-top:20px}

.dochero{background:var(--surface);border-bottom:1px solid var(--line);padding-block:0 30px}
.dochero img{width:100%;max-width:820px;height:auto;display:block;border-radius:14px;
  border:1px solid var(--line);box-shadow:var(--shadow)}
.dochero .cap{font-family:"Archivo",sans-serif;font-size:13.5px;color:var(--muted);margin:11px 0 0}

.doc{display:grid;grid-template-columns:212px minmax(0,1fr);gap:64px;
  padding-block:44px 64px;align-items:start}
.doc.nosidebar{grid-template-columns:minmax(0,1fr);max-width:72ch}
@media(max-width:940px){.doc{grid-template-columns:minmax(0,1fr);gap:0}}

.toc{position:sticky;top:96px;padding-right:8px}
@media(max-width:940px){
  .toc{position:static;margin-bottom:30px;padding:18px 20px;background:var(--surface);
    border:1px solid var(--line);border-radius:12px}
}
.toc-h{font-family:"IBM Plex Mono",monospace;font-size:11px;letter-spacing:1.1px;text-transform:uppercase;
  color:var(--muted);margin:0 0 12px;padding-bottom:10px;border-bottom:1px solid var(--line)}
.toc a{display:block;font-family:"Archivo",sans-serif;font-size:14px;line-height:1.4;color:var(--ink-2);
  text-decoration:none;padding:7px 0 7px 13px;border-left:2px solid var(--line)}
.toc a:hover{color:var(--accent);border-left-color:var(--accent);background:var(--accent-soft)}

.doc-body{max-width:70ch}
.doc-body > h2{font-size:26px;letter-spacing:-.5px;font-weight:700;margin:44px 0 14px;
  scroll-margin-top:96px;text-wrap:balance}
.doc-body > h2:first-child{margin-top:0}
.doc-body > h2::before{content:"";display:block;width:34px;height:3px;border-radius:2px;
  background:var(--accent);margin-bottom:14px}
.doc-body h3{font-size:19px;font-weight:600;margin:30px 0 8px;letter-spacing:-.2px}
.doc-body p{margin:0 0 16px;font-size:17px;line-height:1.72}
.doc-body ul,.doc-body ol{margin:0 0 18px;padding-left:22px}
.doc-body li{margin-bottom:10px;line-height:1.66}
.doc-body li::marker{color:var(--accent)}
.doc-body > p:first-of-type{font-size:19px;line-height:1.65;color:var(--ink-2)}
.doc-body .ph{white-space:nowrap}
.doc-body .cluster{margin-top:8px}
.doc-body .tl{background:var(--surface);border:1px solid var(--line);border-radius:12px;
  padding:6px 20px;margin:20px 0 22px}
.doc-body .tl li{border-top-color:var(--line);padding:11px 0}
.doc-body .srcs li{padding:10px 0}

/* doc refinements */
.doc{max-width:1000px;margin-inline:auto}
.doc.nosidebar{margin-inline:auto}
.dochero img{margin-inline:auto;max-width:880px}
.dochero .cap{text-align:center;max-width:880px;margin-inline:auto}
.doc-body .ph{background:var(--flag-soft);color:var(--flag);padding:1px 7px;border-radius:5px;
  font-family:"IBM Plex Mono",monospace;font-size:14.5px;white-space:nowrap}
.doc-body strong{color:var(--ink);font-weight:600}
.doc-body a{text-decoration:underline;text-underline-offset:2px;text-decoration-thickness:1px}
.doc-body .cluster a{text-decoration:none}

/* ===== homepage bands ===== */
.band{width:100%}
.band-cats{background:var(--surface);border-block:1px solid var(--line)}
.band-surface{background:var(--surface);border-block:1px solid var(--line)}
.band-dark{background:var(--ink)}
.band-dark .statrow{background:transparent;border:0;box-shadow:none;border-radius:0}
.band-dark .statrow > div{border-right:1px solid rgba(255,255,255,.12);min-height:96px;padding:6px 18px}
.band-dark .statrow > div:last-child{border-right:0}
.band-dark .statrow .n{color:#8FC0AF}
.band-dark .statrow .l{color:#AEBCCB}
.statsec{padding-block:38px}
@media(max-width:620px){
  .band-dark .statrow > div{border-right:0;border-top:1px solid rgba(255,255,255,.12)}
  .band-dark .statrow > div:first-child{border-top:0}
}
.band-cats .cat .ic,.band-cats .cat .pill,.band-cats .quick a{background:var(--surface)}

/* ---------- article extras: sources, callouts, tables, spelling tool, learn index */
.doc-body ol.refs{font-family:"Archivo",sans-serif;font-size:14px;color:var(--muted);padding-left:24px;
  border-top:1px solid var(--line);padding-top:14px}
.doc-body ol.refs li{margin-bottom:8px;line-height:1.55}
.doc-body ol.refs li::marker{color:var(--muted);font-family:"IBM Plex Mono",monospace;font-size:12px}
.doc-body ol.refs a{color:var(--ink-2)}
.doc-body code{font-family:"IBM Plex Mono",monospace;font-size:.88em;background:var(--accent-soft);
  color:var(--ink);padding:1px 6px;border-radius:5px;white-space:nowrap}
.doc-body .tbl-wrap table.data{min-width:560px}
.doc-body .tbl-wrap td,.doc-body .tbl-wrap th{font-size:15px;line-height:1.5;vertical-align:top}
table.data.letters{min-width:560px}
table.data.letters th[scope=row],table.data.letters th[scope=col]{text-align:left;white-space:nowrap}
table.data.letters td{text-align:center;font-family:"IBM Plex Mono",monospace;font-size:17px;padding:10px 6px}
.callout{background:var(--accent-soft);border-left:4px solid var(--accent);border-radius:0 12px 12px 0;
  padding:18px 22px;margin:24px 0}
.callout .callout-h{font-family:"Archivo",sans-serif;font-size:12px;letter-spacing:.8px;text-transform:uppercase;
  font-weight:700;color:var(--accent);margin:0 0 8px}
.doc-body .callout p{font-size:16px}
.doc-body .callout p:last-child{margin-bottom:0}
.spell{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:20px 22px;margin:24px 0;
  font-family:"Archivo",sans-serif}
.spell label{display:block;font-size:12px;letter-spacing:.8px;text-transform:uppercase;font-weight:700;
  color:var(--muted);margin-bottom:8px}
.spell input{width:100%;max-width:340px;height:46px;font-size:18px;padding:0 14px;border:1px solid var(--line);
  border-radius:10px;background:var(--surface-2);color:var(--ink);font-family:"Archivo",sans-serif}
.spell input:focus{outline:2px solid var(--accent);outline-offset:1px}
.spell-out{display:flex;flex-wrap:wrap;align-items:center;gap:10px 18px;margin-top:16px}
.spell-num{font-family:"IBM Plex Mono",monospace;font-size:30px;font-weight:500;letter-spacing:2px;
  background:#1d2a1f;color:#b9f5a6;padding:8px 18px;border-radius:8px;min-width:150px;text-align:right}
.spell-note{font-size:14px;color:var(--muted)}
.learn-grid{grid-template-columns:repeat(auto-fill,minmax(280px,1fr))}
.learn-grid a{padding:18px 20px}
.learn-grid .t{font-size:17px}
.cluster .t,.cluster .d{display:block}
.nosidebar .learn-grid{max-width:none}

/* ---------- article depth: worked steps, quick answers, figures, word lists */
.work{background:var(--surface);border:1px solid var(--line);border-radius:12px;margin:18px 0 22px;overflow:hidden}
.work > div{display:flex;justify-content:space-between;align-items:baseline;gap:16px;padding:11px 18px;
  border-top:1px solid var(--line)}
.work > div:first-child{border-top:0}
.work span{font-family:"IBM Plex Mono",monospace;font-size:16px;color:var(--ink)}
.work em{font-family:"Archivo",sans-serif;font-style:normal;font-size:12.5px;color:var(--muted);text-align:right}
.work > div:last-child{background:var(--accent-soft)}
.doc-body .qa h3{font-family:"Archivo",sans-serif;font-size:17px;margin:22px 0 6px}
.doc-body .qa h3:first-child{margin-top:4px}
.doc-body .qa p{font-size:16px;margin-bottom:0}
.figsvg{margin:22px 0 26px}
.figsvg figcaption{font-family:"Archivo",sans-serif;font-size:13px;color:var(--muted);margin-top:10px;line-height:1.5}
.segpair{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.segpair > div{display:flex;flex-direction:column;gap:8px}
.segpair .cap{font-family:"Archivo",sans-serif;font-size:11px;letter-spacing:.8px;text-transform:uppercase;font-weight:700;color:var(--muted)}
.segpair figcaption{grid-column:1/-1;margin-top:0}
@media(max-width:560px){.segpair{grid-template-columns:1fr}}
svg.seg{display:block;width:100%;height:auto;max-width:360px}
svg.seg .lcd{fill:#1d2a1f}
svg.seg line{stroke-width:6.5;stroke-linecap:round}
svg.seg .on{stroke:#b9f5a6;fill:#b9f5a6}
svg.seg .off{stroke:rgba(185,245,166,.08)}
svg.segbig{max-width:170px}
svg.seg .seglab{font-family:"IBM Plex Mono",monospace;font-size:11px;fill:#f0c35a;text-anchor:middle;dominant-baseline:middle;font-weight:600}
svg.soroban{display:block;width:100%;max-width:300px;height:auto}
svg.soroban .frame{fill:#6b4a2b;stroke:#4a321c;stroke-width:3}
svg.soroban .bar{stroke:#3a2714;stroke-width:5}
svg.soroban .rod{stroke:#caa877;stroke-width:3}
svg.soroban .bead{fill:#a98563;stroke:#4a321c;stroke-width:1.5}
svg.soroban .bead.on{fill:#f0c35a}
svg.soroban .lbl{font-family:"IBM Plex Mono",monospace;font-size:15px;fill:var(--ink);text-anchor:middle}
.doc-body ul.wordlist{list-style:none;padding:0;margin:8px 0 22px;display:grid;
  grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:6px}
.doc-body ul.wordlist li{margin:0;display:flex;justify-content:space-between;gap:8px;align-items:baseline;
  background:var(--surface);border:1px solid var(--line);border-radius:8px;padding:7px 11px}
.wordlist .w{font-family:"Archivo",sans-serif;font-size:15px;color:var(--ink)}
.wordlist .c{font-family:"IBM Plex Mono",monospace;font-size:13.5px;color:var(--muted)}
.doc-body ul.stats{list-style:none;padding:0;margin:14px 0 22px;display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
@media(max-width:600px){.doc-body ul.stats{grid-template-columns:1fr}}
.doc-body ul.stats li{margin:0;background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:16px 18px}
.stats .n{display:block;font-family:"Archivo",sans-serif;font-size:30px;font-weight:700;color:var(--accent);letter-spacing:-.5px}
.stats .l{display:block;font-family:"Archivo",sans-serif;font-size:13.5px;color:var(--muted);margin-top:4px;line-height:1.45}
.doc-body .cluster + p{margin-top:20px}