/* Notchline site. Tokens from packages/design_system/lib/src/palette.dart: "Pine" (pale pine page,
   paper cards, pencil-graphite ink, chalk-line blue as the one accent) by day, "Graphite" (pencil
   lead grey, steel lines, a blue that does not glare) in dark mode, and "Sun" for high contrast
   (every text pair ≥ 7:1). One family, Work Sans (SIL OFL 1.1), as in the app, self-hosted (licence
   beside it). No external requests. Status is never colour alone: icon + word + colour. Touch
   targets ≥ 48 px. Copied from Boxwright tools/site/static/site.css (studio §12) and recoloured. */

@font-face { font-family: "Work Sans"; src: url(fonts/WorkSans-Regular.ttf) format("truetype"); font-weight: 400; font-display: swap; }
@font-face { font-family: "Work Sans"; src: url(fonts/WorkSans-SemiBold.ttf) format("truetype"); font-weight: 600 700; font-display: swap; }

:root{
  --bg:#F2ECDF;
  --surface:#FCFAF5;
  --surface2:#E9E1D0;
  --line:#D5CAB3;
  --text:#1E2126;
  --text2:#454A52;
  --text3:#575C64;
  --accent:#15529F;
  --fill:#1B62BE;
  --on-fill:#FFFFFF;
  --fill-soft:#DDE7F4;
  --wood:#E6C990;
  --wood-edge:#7E5A28;
  --slab:#CFC7B8;
  --steel:#59616B;
  --ok:#276636;
  --ok-soft:#DCEBDC;
  --warn:#8E4D00;
  --warn-soft:#F4E3C8;
  --out:#AB232B;
  --out-soft:#F5DAD7;
  --info:#365775;
  --info-soft:#DDE6EE;
  --slate:#22252A;
  --chalk:#F5F2EB;
  --line-w:1px;
  --radius:14px;
  --sans:"Work Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
@media (prefers-color-scheme:dark){
  :root{
    --bg:#141619;
    --surface:#1D2024;
    --surface2:#272B30;
    --line:#383D44;
    --text:#EAE7E0;
    --text2:#C3C0B9;
    --text3:#A5A29B;
    --accent:#8DBBF4;
    --fill:#77AEF2;
    --on-fill:#0A1729;
    --fill-soft:#1D2A3C;
    --wood:#6B4F2B;
    --wood-edge:#D9B67C;
    --slab:#3A3E44;
    --steel:#9BA4AE;
    --ok:#8ECC9A;
    --ok-soft:#1C2E21;
    --warn:#F0B263;
    --warn-soft:#352816;
    --out:#F4928D;
    --out-soft:#3C1E1E;
    --info:#AAC2D9;
    --info-soft:#212B36;
    --slate:#353940;
    --chalk:#F2EFE8;
  }
}
@media (prefers-contrast:more){
  :root{
    --bg:#FFFFFF;
    --surface:#FFFFFF;
    --surface2:#F1EFEA;
    --line:#000000;
    --text:#000000;
    --text2:#1A1A1A;
    --text3:#262626;
    --accent:#0A3E8C;
    --fill:#0A3E8C;
    --on-fill:#FFFFFF;
    --fill-soft:#E4ECF8;
    --wood:#EDCF95;
    --wood-edge:#6E4A18;
    --slab:#BDBDBD;
    --steel:#262A30;
    --ok:#134F20;
    --ok-soft:#E3F0E3;
    --warn:#5A3100;
    --warn-soft:#FAEDDA;
    --out:#780A12;
    --out-soft:#FAE4E4;
    --info:#12324F;
    --info-soft:#E5ECF2;
    --slate:#000000;
    --chalk:#FFFFFF;
    --line-w:2px;
  }
}

*,*::before,*::after{box-sizing:border-box}
[hidden]{display:none!important}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--text);overflow-wrap:break-word;font:400 1.125rem/1.6 var(--sans);font-variant-numeric:tabular-nums}
img,svg{max-width:100%;height:auto}
a{color:var(--accent);text-underline-offset:.18em;text-decoration-thickness:1px}
a:hover{text-decoration-thickness:2px}
:focus-visible{outline:3px solid var(--fill);outline-offset:2px;border-radius:4px}
h1,h2,h3,.h3{font-family:var(--sans);font-weight:600;line-height:1.08;hyphens:auto;overflow-wrap:break-word;color:var(--text);font-variant-numeric:lining-nums;text-wrap:balance}
h1{font-size:clamp(2.1rem,1.5rem + 2.8vw,3.4rem);margin:.2em 0 .35em;letter-spacing:-.01em}
h2{font-size:clamp(1.55rem,1.3rem + 1vw,2.1rem);margin:1.6em 0 .5em}
h3,.h3{font-size:1.3rem;margin:1.3em 0 .4em}
p{margin:0 0 1em}
ul,ol{padding-left:1.3em}
li{margin:.25em 0}
small,.small{font-size:.95rem}
code,.mono{font-family:var(--sans);font-weight:600;background:var(--surface2);border-radius:6px;padding:0 .3em}
.wrap{max-width:1120px;margin:0 auto;padding:0 16px}
@media (min-width:720px){.wrap{padding:0 28px}}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.skip{position:absolute;left:12px;top:-60px;background:var(--fill);color:var(--on-fill);padding:12px 16px;border-radius:10px;z-index:9;font-weight:700}
.skip:focus{top:12px}
main{display:block;padding-bottom:48px}
main:focus{outline:none}
.gap-top{margin-top:48px}
.narrow{max-width:62ch}
.lead{font-size:1.25rem;color:var(--text2);max-width:62ch}
.note{color:var(--text2);font-size:1rem}

/* header */
.top{background:var(--bg);border-bottom:var(--line-w) solid var(--line)}
.top .wrap{display:flex;align-items:center;gap:8px 18px;min-height:64px;flex-wrap:wrap}
.brand{display:inline-flex;align-items:center;gap:10px;font:600 1.4rem/1 var(--sans);letter-spacing:-.01em;color:var(--text);text-decoration:none;min-height:48px;margin-right:auto}
.brand img{width:32px;height:32px}
nav.main{display:flex;gap:4px;flex-wrap:wrap}
nav.main a{display:inline-flex;align-items:center;min-height:48px;padding:0 12px;border-radius:10px;color:var(--text);text-decoration:none;font-weight:600}
nav.main a:hover{background:var(--surface2)}
nav.main a[aria-current]{background:var(--fill-soft);color:var(--text);box-shadow:inset 0 -3px 0 var(--fill)}
.langpick{position:relative}
.langpick summary{list-style:none;display:inline-flex;align-items:center;gap:6px;min-height:48px;min-width:48px;padding:0 12px;border-radius:10px;cursor:pointer;font-weight:700;color:var(--text)}
.langpick summary::-webkit-details-marker{display:none}
.langpick summary svg{width:20px;height:20px}
.langpick summary:hover{background:var(--surface2)}
.langpick nav{position:absolute;right:0;top:100%;z-index:5;background:var(--surface);border:var(--line-w) solid var(--line);border-radius:12px;padding:6px;min-width:210px;box-shadow:0 12px 32px rgb(0 0 0 / .18)}
.langpick nav a{display:flex;align-items:center;min-height:48px;padding:0 12px;border-radius:8px;color:var(--text);text-decoration:none}
.langpick nav a:hover{background:var(--surface2)}
.langpick nav a[aria-current]{font-weight:700;background:var(--fill-soft)}
@media (max-width:560px){nav.main{order:3;width:100%;margin:0 -12px}}

/* hero */
.hero{display:grid;gap:32px;align-items:center;padding:40px 0 8px}
@media (min-width:900px){.hero{grid-template-columns:1.15fr .85fr;padding-top:64px}}
.eyebrow{display:inline-block;font-weight:700;color:var(--accent);letter-spacing:.06em;text-transform:uppercase;font-size:.9rem;margin:0}
.promise{list-style:none;padding:0;display:flex;flex-wrap:wrap;gap:8px 20px;margin:18px 0 0}
.promise li{display:flex;align-items:center;gap:8px;font-weight:600;margin:0}
.promise svg,.ticks svg{width:20px;height:20px;flex:none;color:var(--ok)}

/* store badges */
.stores{display:flex;flex-wrap:wrap;gap:12px;margin:22px 0 4px}
.store{display:inline-flex;flex-direction:column;justify-content:center;min-height:56px;min-width:168px;padding:6px 18px;border-radius:12px;background:var(--slate);color:var(--chalk);text-decoration:none;line-height:1.15}
.store small{font-size:.8rem;opacity:.9}
.store b{font-size:1.15rem}
.store.soon{background:transparent;color:var(--text);border:2px dashed var(--line)}
@media (prefers-contrast:more){.store.soon{border-color:var(--text)}}

/* cards */
.card{background:var(--surface);border:var(--line-w) solid var(--line);border-radius:var(--radius);padding:22px}
.features{display:grid;gap:16px}
@media (min-width:700px){.features{grid-template-columns:repeat(2,1fr)}}
@media (min-width:1000px){.features{grid-template-columns:repeat(3,1fr)}}
.feature h3{margin:.5em 0 .3em}
.feature p{margin:0;color:var(--text2)}
.ficon{display:inline-flex;width:44px;height:44px;border-radius:12px;background:var(--fill-soft);color:var(--accent);align-items:center;justify-content:center}
.ficon svg{width:24px;height:24px}
.tiers,.split{display:grid;gap:16px}
@media (min-width:800px){.tiers,.split{grid-template-columns:1fr 1fr}}
.ticks{list-style:none;padding:0;margin:0}
.ticks li{display:flex;gap:10px;align-items:flex-start;margin:.45em 0}
.ticks svg{margin-top:4px}
.pro{border-color:var(--fill);border-width:2px}
.pro-note{margin:14px 0 0;color:var(--text2)}

/* specimen: a stair the way the app draws it */
.specimen{margin:0;padding:20px}
.sp-head{display:flex;flex-wrap:wrap;align-items:center;gap:8px 12px}
.sp-tag{background:var(--fill);color:var(--on-fill);font:700 1rem/1 var(--sans);padding:8px 10px;border-radius:6px;letter-spacing:.02em}
.sp-name{font:600 1.3rem/1.2 var(--sans)}
.sp-draw{display:block;width:100%;margin:14px 0 6px;background:var(--surface2);border-radius:10px}
.sp-draw .slab{fill:var(--slab)}
.sp-draw .wood{fill:var(--wood);stroke:var(--wood-edge);stroke-width:1.4;stroke-linejoin:round}
.sp-draw .nosing{stroke:var(--steel);stroke-width:1;stroke-dasharray:4 3;fill:none}
.sp-draw .dim{stroke:var(--steel);stroke-width:1.2;fill:none}
.sp-draw .head{stroke:var(--ok);stroke-width:2;fill:none}
.sp-draw .dimtag{fill:var(--fill)}
.sp-draw text{font:700 11px var(--sans);fill:var(--on-fill)}
.sp-nums{display:grid;grid-template-columns:repeat(2,1fr);gap:10px 16px;margin:10px 0}
.sp-nums div{margin:0}
.sp-nums dt{color:var(--text2);font-size:.95rem}
.sp-nums dd{margin:0;font:700 1.6rem/1.1 var(--sans);font-variant-numeric:lining-nums tabular-nums}
.sp-nums small{font:600 .95rem var(--sans);color:var(--text2)}
.specimen figcaption{color:var(--text2);font-size:.92rem;margin-top:6px}

/* page cards and next links */
.calc-cards{list-style:none;padding:0;margin:0;display:grid;gap:14px}
@media (min-width:700px){.calc-cards{grid-template-columns:repeat(2,1fr)}}
.calc-cards li{margin:0}
.calc-card{display:flex;flex-direction:column;gap:6px;height:100%;text-decoration:none;color:var(--text);min-height:48px}
.calc-card:hover{border-color:var(--fill)}
.cc-h{display:flex;align-items:center;gap:8px;font:700 1.3rem/1.2 var(--sans);color:var(--text)}
.cc-h svg{width:20px;height:20px;color:var(--accent);flex:none}
.cc-p{color:var(--text2)}
.next{margin:32px 0 0}
.next-h{font-weight:700;margin:0 0 6px}
.next ul{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:8px}
.next li{margin:0}
.next a{display:inline-flex;align-items:center;gap:8px;min-height:48px;padding:0 16px;border-radius:999px;border:var(--line-w) solid var(--line);background:var(--surface);text-decoration:none;color:var(--text);font-weight:600}
.next a svg{width:18px;height:18px;color:var(--accent)}
.next a:hover{border-color:var(--fill)}
.crumb{margin:28px 0 0;color:var(--text2)}
.crumb a{display:inline-block;padding:12px 0;color:var(--text2)}
.also-in{display:flex;flex-wrap:wrap;align-items:center;gap:4px 14px;margin:40px 0 0;padding-top:16px;border-top:var(--line-w) solid var(--line);color:var(--text2)}
.also-in a{display:inline-flex;align-items:center;min-height:48px}

/* calculators */
.calc{display:grid;gap:20px;margin-top:20px}
.calc>*,.field-row>*{min-width:0}
@media (min-width:900px){.calc{grid-template-columns:1fr 1fr;align-items:start}.calc .results{position:sticky;top:16px}}
.panel{background:var(--surface);border:var(--line-w) solid var(--line);border-radius:var(--radius);padding:20px}
.field{margin:0 0 18px}
.field label,legend{display:block;font-weight:700;margin:0 0 6px}
.field input,.field select{font:inherit;color:var(--text);background:var(--surface2);border:2px solid var(--text3);border-radius:10px;min-height:52px;padding:8px 12px;width:100%}
.field input{font-size:1.3rem;font-variant-numeric:tabular-nums slashed-zero}
.joined{display:flex;gap:8px;align-items:center}
.joined input{flex:1 1 auto;min-width:0}
.unit{flex:none;min-width:3.2em;font-weight:700;color:var(--text2)}
.field input[aria-invalid]{border-color:var(--out)}
.hint{display:block;color:var(--text2);font-size:.98rem;margin-top:4px}
.err{display:block;color:var(--out);font-weight:700;margin-top:4px}
.err::before{content:"✕ ";font-weight:700}
.field-row{display:grid;gap:0 14px}
@media (min-width:520px){.field-row.two{grid-template-columns:1fr 1fr}.field-row.three{grid-template-columns:1fr 1fr 1fr}}
fieldset.choice{border:0;padding:0;margin:0 0 18px;min-width:0}
.pills{display:flex;flex-wrap:wrap;gap:8px}
.pill{position:relative;display:inline-flex}
.pill input{position:absolute;opacity:0;inset:0;width:100%;height:100%;margin:0;cursor:pointer}
.pill span{display:inline-flex;align-items:center;min-height:48px;padding:0 16px;border-radius:999px;border:2px solid var(--line);background:var(--surface2);font-weight:600}
.pill input:checked+span{background:var(--fill);border-color:var(--fill);color:var(--on-fill)}
.pill input:checked+span::before{content:"✓";margin-right:6px}
.pill input:focus-visible+span{outline:3px solid var(--accent);outline-offset:2px}
details.more{border-top:var(--line-w) solid var(--line);padding-top:4px;margin-top:4px}
details.more summary,details.faq summary{cursor:pointer;min-height:48px;display:flex;align-items:center;font-weight:700;color:var(--accent)}
details.more[open] summary{margin-bottom:10px}
.res-card{min-height:120px}
.res-card h3{margin-top:0;font:700 1rem/1.3 var(--sans);text-transform:uppercase;letter-spacing:.05em;color:var(--text2)}
.res-card .big{font:700 clamp(2.4rem,1.8rem + 2vw,3.2rem)/1.05 var(--sans);letter-spacing:-.02em;margin:.1em 0 .25em;font-variant-numeric:lining-nums tabular-nums slashed-zero}
.res-what{color:var(--text2)}
.kv{list-style:none;padding:0;margin:8px 0 14px}
.kv li{display:flex;justify-content:space-between;gap:16px;padding:10px 0;margin:0;border-bottom:var(--line-w) solid var(--line)}
.kv li span{color:var(--text2)}
.kv li b{text-align:right;font-variant-numeric:tabular-nums slashed-zero}
.flag{display:flex;gap:10px;align-items:flex-start;padding:12px 14px;border-radius:10px;margin:10px 0}
.flag svg{width:22px;height:22px;flex:none;margin-top:2px}
.flag.warn{background:var(--warn-soft);color:var(--text)}
.flag.warn svg,.flag.warn .flag-word{color:var(--warn)}
.flag.stop{background:var(--out-soft);color:var(--text)}
.flag.stop svg,.flag.stop .flag-word{color:var(--out)}
.flag.info{background:var(--info-soft);color:var(--text)}
.flag.info svg,.flag.info .flag-word{color:var(--info)}
.flag.good{background:var(--ok-soft);color:var(--text)}
.flag.good svg,.flag.good .flag-word{color:var(--ok)}
.how{border-left:3px solid var(--fill);padding:4px 0 4px 14px;margin:16px 0 8px;font-size:1rem}
.how-h{font-weight:700;margin-bottom:4px}
.how p{margin:0 0 .4em;color:var(--text2)}
.mini{margin:12px 0 0}

/* rule rows: icon + word + colour, never colour alone */
.rules{list-style:none;padding:0;margin:8px 0 0}
.rules li{display:grid;grid-template-columns:28px 1fr;gap:4px 10px;padding:10px 0;margin:0;border-bottom:var(--line-w) solid var(--line)}
.rules li svg{width:22px;height:22px;margin-top:2px}
.rules .r-name{font-weight:600}
.rules .r-clause,.rules .r-src{display:block;color:var(--text2);font-size:.95rem}
.rules .r-vals{display:block;font-variant-numeric:tabular-nums}
.rules .r-word{display:block;font-weight:700}
.rules .within svg,.rules .within .r-word{color:var(--ok)}
.rules .outside svg,.rules .outside .r-word{color:var(--out)}
.rules .unchecked svg,.rules .unchecked .r-word{color:var(--text2)}
.opts{display:flex;flex-wrap:wrap;gap:8px;margin:6px 0 12px}
.opts button{font:inherit;font-weight:600;min-height:48px;padding:0 16px;border-radius:999px;border:2px solid var(--line);background:var(--surface2);color:var(--text);cursor:pointer}
.opts button[aria-pressed="true"]{background:var(--fill);border-color:var(--fill);color:var(--on-fill)}
.field select{font-size:1.05rem}

/* prose pages */
.prose{max-width:780px}
.wrap.prose{margin-top:24px}
.prose h1{margin-top:.4em}
.updated{color:var(--text2);font-size:1rem}
.callout{background:var(--fill-soft);border-radius:12px;padding:14px 18px;color:var(--text)}
.callout p{margin:0}
.toc{background:var(--surface);border:var(--line-w) solid var(--line);border-radius:12px;padding:14px 18px;margin:20px 0}
.toc-h{font-weight:700;margin:0 0 4px}
.toc ol{margin:0}
.toc a{display:inline-block;padding:6px 0}
.sources{font-size:1rem;color:var(--text2)}
.sources li{margin:.5em 0}
.faq{background:var(--surface);border:var(--line-w) solid var(--line);border-radius:12px;padding:4px 18px;margin:10px 0}
.faq[open]{padding-bottom:12px}
.app-note{margin-top:32px}
.app-note h2{margin-top:0}
.link-list{list-style:none;padding:0}
.link-list a{display:inline-flex;align-items:center;min-height:48px}
.table-wrap{overflow-x:auto;border:var(--line-w) solid var(--line);border-radius:12px;background:var(--surface);margin:12px 0 20px}
.num-table{border-collapse:collapse;width:100%;font-variant-numeric:tabular-nums slashed-zero;font-size:1rem}
.table-cap{font-weight:700;margin:20px 0 6px}
.table-cap+.table-wrap{margin-top:0}
.num-table th,.num-table td{padding:8px 12px;text-align:right;border-bottom:var(--line-w) solid var(--line);white-space:nowrap}
.num-table thead th{background:var(--surface2)}
.num-table th:first-child,.num-table td:first-child,.num-table .l{text-align:left;white-space:normal;min-width:9.5em}
.num-table tbody tr:nth-child(even)>*{background:var(--surface2)}
.ok-mark{color:var(--ok);font-weight:700}

/* footer */
footer{border-top:var(--line-w) solid var(--line);padding:28px 0 40px;color:var(--text2);font-size:1rem}
footer .disclaimer{font-weight:700;color:var(--text)}
footer nav{display:flex;flex-wrap:wrap;gap:0 18px}
footer nav a{display:inline-flex;align-items:center;min-height:48px;color:var(--text2)}

@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important;scroll-behavior:auto!important}}
@media print{
  .top,footer,.calc,.next,.app-note,.also-in,.crumb,.skip{display:none}
  body{background:#fff;color:#000;font-size:11pt}
  .table-wrap{border:0;overflow:visible}
}