/* Self-hosted Archivo variable font — one 35 KB request covers weights 100-900. */
@font-face{
  font-family:"Archivo";
  src:url("fonts/archivo-variable.woff2") format("woff2") tech(variations),
      url("fonts/archivo-variable.woff2") format("woff2-variations");
  font-weight:100 900;
  font-style:normal;
  font-display:swap;
}
/* Metrics-matched fallback: the first paint uses a local grotesque scaled to
   Archivo's proportions, so swapping in the real face causes no layout shift. */
@font-face{
  font-family:"Archivo Fallback";
  src:local("Helvetica Neue"),local("Arial"),local("Liberation Sans");
  size-adjust:97%;
  ascent-override:92%;
  descent-override:24%;
  line-gap-override:0%;
}
:root{
  --color-bg:#f3f2f2;--color-surface:#eae9e9;--color-text:#201e1d;--color-accent:#ec3013;
  --color-divider:color-mix(in srgb,#201e1d 40%,transparent);
  --color-neutral-100:#f8f4f4;--color-neutral-800:#444141;
  --color-accent-100:#fff2ef;--color-accent-600:#dd2b0f;--color-accent-700:#ae1800;--color-accent-800:#7c1405;
  --font-heading:"Archivo","Archivo Fallback",system-ui,sans-serif;--font-heading-weight:800;--font-body:"Archivo","Archivo Fallback",system-ui,sans-serif;
  --space-1:4px;--space-2:8px;--space-3:12px;--space-4:16px;--radius-md:0px;
}
*,*::before,*::after{box-sizing:border-box}
body{margin:0;background:var(--color-bg);color:var(--color-text);font-family:var(--font-body);font-size:15px;line-height:1.55;-webkit-text-size-adjust:100%}
h1,h2,h3{font-family:var(--font-heading);font-weight:var(--font-heading-weight);line-height:1.12;letter-spacing:-0.015em;margin:0 0 var(--space-2)}
p{margin:0 0 var(--space-3)}
a{color:var(--color-accent-700);text-decoration:none;text-underline-offset:3px}
a:hover{color:var(--color-accent);text-decoration:underline}
:focus{outline:none}
:focus-visible{outline:2px solid var(--color-accent);outline-offset:2px}
::selection{background:color-mix(in srgb,var(--color-accent) 30%,transparent)}
::-webkit-scrollbar{width:10px;height:10px}
::-webkit-scrollbar-thumb{background:color-mix(in srgb,var(--color-text) 28%,transparent)}
::-webkit-scrollbar-track{background:color-mix(in srgb,var(--color-text) 6%,transparent)}
.input{width:100%;min-height:36px;padding:6px 10px;font:inherit;font-size:14px;color:var(--color-text);caret-color:var(--color-accent);background:var(--color-surface);border:1px solid var(--color-divider);border-radius:var(--radius-md)}
.input:hover{border-color:color-mix(in srgb,var(--color-text) 45%,transparent)}
.input:focus-visible{border-color:var(--color-accent);outline-offset:0}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;cursor:pointer;font-family:var(--font-heading);font-weight:800;font-size:14px;line-height:1.2;color:var(--color-text);background:transparent;border:1px solid transparent;padding:var(--space-2) 14px;border-radius:0}
.btn-primary{background:var(--color-accent);color:var(--color-bg)}
.btn-primary:hover{background:var(--color-accent-600)}
.btn-ghost{color:var(--color-accent);padding-inline:var(--space-1)}
.btn-ghost:hover{background:color-mix(in srgb,var(--color-accent) 10%,transparent)}
.muted{color:color-mix(in srgb,var(--color-text) 55%,transparent)}
.shell{max-width:1120px;margin:0 auto;background:#fff;min-height:100vh;border-left:1px solid var(--color-divider);border-right:1px solid var(--color-divider)}
.head{display:flex;align-items:baseline;gap:12px;padding:14px 16px;border-bottom:2px solid var(--color-divider);flex-wrap:wrap}
.brand{font-family:var(--font-heading);font-weight:800;font-size:20px;letter-spacing:-0.02em}
.kicker{font-size:11px;letter-spacing:.1em;text-transform:uppercase}
.intro{padding:20px 16px 18px;border-bottom:2px solid var(--color-divider)}
.intro h1{font-size:clamp(26px,7vw,40px);margin:0 0 8px;letter-spacing:-.025em}
.intro p{margin:0 0 14px;max-width:62ch;text-wrap:pretty}
.steps{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1px;background:var(--color-divider);border:1px solid var(--color-divider)}
.step{background:#fff;padding:10px 12px}
.step b{display:block;font-size:10px;letter-spacing:.1em;text-transform:uppercase;color:var(--color-accent);font-weight:600}
.step span{font-size:13.5px;line-height:1.4}
.adtag{font-size:9px;letter-spacing:.14em;text-transform:uppercase;border:1px solid currentColor;padding:2px 6px}
.ad-top{border-bottom:2px solid var(--color-divider);background:var(--color-accent);color:#fff;padding:12px 16px;display:flex;gap:14px;align-items:center;flex-wrap:wrap}
.ad-top strong{font-family:var(--font-heading);font-weight:800;font-size:clamp(16px,4.4vw,22px);letter-spacing:-.02em}
.ad-mid{padding:14px 16px;border-top:2px solid var(--color-divider);border-bottom:2px solid var(--color-divider);background:var(--color-accent-100);display:flex;gap:14px;align-items:center;flex-wrap:wrap}
.ad-mid strong{font-family:var(--font-heading);font-weight:800;font-size:17px;letter-spacing:-.02em}
.ad-foot{border-top:2px solid var(--color-divider);padding:14px 16px;display:flex;gap:12px;align-items:center;flex-wrap:wrap;background:var(--color-surface);font-size:13px}
nav.tabs{border-bottom:2px solid var(--color-divider);overflow-x:auto}
nav.tabs div{display:flex;min-width:max-content}
.tab{appearance:none;border:0;border-right:1px solid var(--color-divider);cursor:pointer;padding:12px 16px;min-height:46px;font-family:var(--font-heading);font-weight:800;font-size:13px;letter-spacing:.02em;text-transform:uppercase;background:#fff;color:var(--color-text)}
.tab:hover{filter:brightness(.97)}
.tab[aria-selected="true"]{background:var(--color-text);color:#fff}
.tab i{font-style:normal;font-weight:400;font-size:10px;opacity:.75}
.defrow{display:flex;align-items:center;gap:10px;padding:8px 16px;border-bottom:1px solid var(--color-divider);flex-wrap:wrap;font-size:12px}
.card{padding:16px}
.cardhead{display:flex;align-items:baseline;gap:10px;margin-bottom:12px;flex-wrap:wrap}
.cardhead h2{font-size:22px;margin:0}
.pxopts[hidden]{display:none}
.pxopts{display:flex;align-items:center;gap:10px;flex-wrap:wrap;margin:-4px 0 14px;padding:8px 10px;border:1px solid var(--color-divider);background:var(--color-accent-100);font-size:12.5px}
.pxopts label{font-size:11px;letter-spacing:.08em;text-transform:uppercase;font-weight:600}
.pxopts .input{width:88px;min-height:36px;background:#fff}
.cols{display:flex;flex-wrap:wrap;gap:14px;align-items:stretch}
.box{border:2px solid var(--color-text);background:#fff;display:flex;flex-direction:column;min-width:0}
.box-from{flex:1 1 250px}
.box-res{flex:2 1 320px}
.mid{flex:1 1 190px;min-width:0;display:flex;flex-direction:column;justify-content:center;gap:10px}
.mid label{font-size:11px;letter-spacing:.08em;text-transform:uppercase;font-weight:600}
#value{min-height:56px;font-size:24px;font-family:var(--font-heading);font-weight:800;border-width:2px;border-color:var(--color-text)}
.eq{display:flex;align-items:center;gap:10px}
.eq span:first-child{font-family:var(--font-heading);font-weight:800;font-size:34px;line-height:1;color:var(--color-accent)}
.searchwrap{padding:8px;border-bottom:2px solid var(--color-text)}
.collabel{padding:6px 10px;font-size:10px;letter-spacing:.1em;text-transform:uppercase;border-bottom:1px solid var(--color-divider)}
.scroll{max-height:440px;overflow-y:auto;flex:1 1 auto}
.urow{appearance:none;width:100%;text-align:left;border:0;border-bottom:1px solid var(--color-divider);cursor:pointer;display:flex;align-items:baseline;gap:8px;padding:0 12px;min-height:46px;font-family:var(--font-body);font-size:14.5px;background:#fff;color:var(--color-text)}
.urow:hover{background:var(--color-accent-100)}
.urow[aria-pressed="true"]{background:var(--color-accent);color:#fff}
.urow span:first-child{font-weight:400}
.urow[aria-pressed="true"] span:first-child{font-weight:700}
.urow em{margin-left:auto;font-style:normal;font-size:12px;opacity:.7}
.rhead,.rrow{display:grid;grid-template-columns:minmax(0,calc(var(--vch,14) * 1ch + 22px)) minmax(0,1fr)}
.rhead{border-bottom:2px solid var(--color-text)}
.rhead .a{padding:7px 10px;display:flex;align-items:center;gap:6px;border-right:1px solid var(--color-divider);flex-wrap:wrap}
.rhead .b{padding:7px 10px;display:flex;align-items:center;font-size:11px;letter-spacing:.08em;text-transform:uppercase;font-weight:700}
.stepper{display:inline-flex;align-items:center;border:1px solid var(--color-text)}
.stepper button{appearance:none;border:0;background:transparent;cursor:pointer;width:30px;height:30px;font-size:17px;font-weight:700;line-height:1}
.stepper button:hover{background:var(--color-accent-100)}
.stepper output{min-width:26px;text-align:center;font-family:var(--font-heading);font-weight:800;font-size:14px}
.rrow{border-bottom:1px solid var(--color-divider);min-height:46px}
.rrow .v{padding:8px 10px;border-right:1px solid var(--color-divider);text-align:left;font-variant-numeric:tabular-nums;font-family:var(--font-heading);font-weight:800;font-size:15px;overflow-wrap:anywhere;line-height:1.3}
.rrow .u{padding:8px 10px;display:flex;align-items:baseline;gap:6px;font-size:14px;white-space:nowrap}
.rrow .u em{font-style:normal;font-size:11px;opacity:.65}
.about{padding:20px 16px}
.about h2{font-size:18px;margin:0 0 8px}
.about p{max-width:70ch;font-size:14px;line-height:1.55;text-wrap:pretty}
.links{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:8px;font-size:13px}
.adzone{padding:12px 16px;border-top:2px solid var(--color-divider);border-bottom:2px solid var(--color-divider);background:#fff;display:block}
footer{padding:16px;border-top:1px solid var(--color-divider);font-size:11.5px;display:flex;gap:12px;flex-wrap:wrap}

/* ── static-site additions ── */
.tab{text-decoration:none;display:flex;align-items:center}
.tab:hover{filter:brightness(.97);text-decoration:none;color:var(--color-text)}
.tab[aria-current="page"]{background:var(--color-text);color:#fff}
.answer{font-family:var(--font-heading);font-weight:800;font-size:clamp(18px,4.6vw,26px);letter-spacing:-.02em;margin:0 0 12px}
.formula{font-size:13px;display:flex;align-items:center;gap:8px;flex-wrap:wrap;margin:0}
.formula code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:13px;background:var(--color-accent-100);padding:4px 8px;border:1px solid var(--color-divider)}
.hubgrid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:1px;background:var(--color-divider);border:1px solid var(--color-divider)}
.hubcard{background:#fff;padding:14px;display:flex;flex-direction:column;gap:2px;text-decoration:none;color:var(--color-text);min-height:88px}
.hubcard:hover{background:var(--color-accent-100);text-decoration:none;color:var(--color-text)}
.hubcard b{font-family:var(--font-heading);font-weight:800;font-size:17px;letter-spacing:-.02em}
.hubcard span{font-size:11px;letter-spacing:.08em;text-transform:uppercase}
.hubcard em{font-style:normal;font-variant-numeric:tabular-nums;font-size:13px;margin-top:6px;color:var(--color-accent-700)}
.hubcard.is-default{box-shadow:inset 0 0 0 2px var(--color-accent)}
table.ref{border-collapse:collapse;width:100%;max-width:520px;margin:0 0 22px;font-size:14px}
table.ref caption{text-align:left;font-size:11px;letter-spacing:.08em;text-transform:uppercase;font-weight:700;padding-bottom:8px}
table.ref th,table.ref td{text-align:left;padding:7px 10px;border-bottom:1px solid var(--color-divider);font-variant-numeric:tabular-nums}
table.ref thead th{border-bottom:2px solid var(--color-text);font-family:var(--font-heading);font-weight:800;font-size:12px;letter-spacing:.04em;text-transform:uppercase}
dl.faq{margin:0 0 22px;max-width:70ch}
dl.faq dt{font-family:var(--font-heading);font-weight:800;font-size:15px;margin-top:14px}
dl.faq dd{margin:4px 0 0;font-size:14px;line-height:1.55}
.about .links a{padding:4px 0}

/* ── card separation ── */
.card{margin:16px;padding:16px;background:var(--color-surface);border:2px solid var(--color-text)}
.card .box{background:#fff}
.card .pxopts{background:#fff}
.hubgrid{border:2px solid var(--color-text);background:var(--color-text)}
.hubcard{background:#fff}

.tab-home{border-right:2px solid var(--color-text);color:var(--color-accent)}
.tab-home:hover{background:var(--color-accent-100);color:var(--color-accent)}
.tab-home[aria-current="page"]{background:var(--color-text);color:#fff}

/* ── pair pages ── */
.crumbs{padding:8px 16px;border-bottom:1px solid var(--color-divider);font-size:12px;display:flex;gap:8px;flex-wrap:wrap;align-items:center}
.crumbs span{color:color-mix(in srgb,var(--color-text) 40%,transparent)}
.crumbs strong{font-weight:600}
.pairbox{display:flex;gap:16px;align-items:flex-end;flex-wrap:wrap;padding-bottom:24px}
.pairfield{flex:1 1 200px;min-width:0;display:flex;flex-direction:column;gap:6px;position:relative}
.pairfield label{font-size:11px;letter-spacing:.08em;text-transform:uppercase;font-weight:600}
.pairfield .input{min-height:60px;font-size:26px;font-family:var(--font-heading);font-weight:800;border-width:2px;border-color:var(--color-text);background:#fff}
.pairEq{font-family:var(--font-heading);font-weight:800;font-size:34px;line-height:1;color:var(--color-accent);padding-bottom:14px}
.pairnote{font-size:12.5px;margin:12px 0 0}
.reftables{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:24px;margin-bottom:8px}
.reftables table.ref{max-width:none;margin:0}

/* ── Core Web Vitals ── */
.scroll{contain:content}
.input,.tab,.urow,.btn{font-synthesis:none}

/* ── copy / print / share ── */
.actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}
.btn-act{background:#fff;border:2px solid var(--color-text);min-height:44px;padding:0 14px;font-size:13px;letter-spacing:.02em;text-transform:uppercase}
.btn-act:hover{background:var(--color-accent-100)}
.btn-act:active{background:var(--color-accent);color:#fff;border-color:var(--color-accent)}
.pairnote+.actions{margin-top:16px}

#printroot{display:none}
@media print{
  /* the masthead, page heading and result card are cloned into #printroot and
     everything else is removed from flow, so the job is one page */
  html.printing body > *{display:none !important}
  html.printing body > #printroot{display:block !important}
  #printroot .actions,#printroot .inputalert,#printroot nav,#printroot .steps{display:none !important}
  #printroot .head{display:flex !important;align-items:baseline;gap:10px;padding:0 0 8px;border-bottom:2px solid var(--color-text);margin-bottom:10px}
  #printroot .head .domain{margin-left:auto;font-size:9pt}
  #printroot .brand{font-size:14pt}
  #printroot .kicker{font-size:8pt}
  #printroot .intro{border:0 !important;padding:0 0 10px !important}
  #printroot .intro h1{font-size:21pt;margin:0 0 5px}
  #printroot .intro .answer{font-size:12pt;margin:0 0 6px}
  #printroot .intro p{font-size:9pt;line-height:1.35;margin:0 0 6px;max-width:none}
  #printroot .formula{font-size:8.5pt}
  #printroot .printcap{display:block !important;font-family:var(--font-heading);font-weight:800;font-size:9pt;padding:0 0 6px}
  #printroot .scroll{max-height:none !important;overflow:visible !important}
  #printroot .rrow,#printroot .rtop,#printroot .rhead{min-height:0 !important}
  #printroot .rrow .v,#printroot .rrow .u{padding:3px 8px !important;font-size:9pt !important}
  #printroot .rrow{break-inside:avoid}
  #printroot .box,#printroot .pairbox{border-width:1px}
  #printroot .pairbox{padding-bottom:0}
  #printroot .pairfield .input{min-height:0;font-size:16pt;padding:4px 8px}
/*  #printroot .pairfield .input-placeholder{min-height:0;font-size:9pt;padding:4px 8px}  */
  body{background:#fff}
  @page{margin:12mm}
}

/* ── input validation alert ── */
.pairfield .inputalert{position:absolute;top:100%;left:0;right:0;margin-top:5px}
.inputalert{margin:6px 0 0;font-size:12.5px;font-weight:600;color:var(--color-accent-700);display:flex;gap:6px;align-items:center}
.inputalert::before{content:"!";display:inline-flex;align-items:center;justify-content:center;width:16px;height:16px;background:var(--color-accent);color:#fff;font-size:11px;font-weight:800;flex:none}
.inputalert[hidden]{display:none}
.input[aria-invalid="true"]{border-color:var(--color-accent)}
.maxnote{font-weight:400;text-transform:none;letter-spacing:0;font-size:11px;color:color-mix(in srgb,var(--color-text) 55%,transparent)}

.printcap{display:none}

/* ── brand mark: the two "Unit" words carry different colour ── */
.brand{white-space:nowrap}
.brand-2{color:color-mix(in srgb,var(--color-text) 45%,transparent);font-weight:600}
.brand-3{color:var(--color-accent)}

/* ── result card: value-being-converted row above the header row ── */
.rtop{padding:8px 10px;border-bottom:1px solid var(--color-divider);font-family:var(--font-heading);font-weight:800;font-size:15px;letter-spacing:-.01em;background:var(--color-accent-100);font-variant-numeric:tabular-nums;overflow-wrap:anywhere;min-height:35px}
/* ── domain, top right of every header ── */
.head .domain{margin-left:auto;font-size:12px;letter-spacing:.02em;color:color-mix(in srgb,var(--color-text) 55%,transparent);white-space:nowrap}
.head .domain:hover{color:var(--color-accent)}
@media (max-width:520px){.head .domain{font-size:11px}}
/* Ad containers: the "Ad" label is hidden by default. To show it for layout checks, run document.body.classList.add("show-ad-labels") in the browser console, or add class="show-ad-labels" to <body>. */
[data-ad-slot] .adtag{display:none}
body.show-ad-labels [data-ad-slot] .adtag{display:inline-block}
body.show-ad-labels [data-ad-slot]{outline:1px dashed var(--color-accent);min-height:24px}
/* Unit measurement gears (affiliate block) */
.gear{margin:26px 0 22px;padding:16px;border:1px solid var(--color-divider);background:var(--color-surface)}
.about .gear h2{font-size:18px;margin:0 0 12px}
.gear-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:12px;align-items:stretch}
.gear-card{display:flex;flex-direction:column;gap:6px;padding:12px;border:1px solid var(--color-divider);background:#fff}
.gear-card h3{font-size:15px;margin:0}
.about .gear-card p{font-size:13px;line-height:1.5;margin:0;flex:1}
.gear-cta{align-self:flex-start;margin-top:6px;padding:7px 12px;background:var(--color-accent);color:#fff;font-weight:700;font-size:13px;text-decoration:none}
.gear-cta:hover{filter:brightness(.92)}.gear-cta:focus-visible,.gear-banner:focus-visible{outline:2px solid var(--color-text);outline-offset:2px}
.gear-banner{display:block}.gear-banner img,.gear-html img{display:block;max-width:100%;height:auto}
.about .gear-note{font-size:12px;margin:12px 0 0}
/* Guide article elements */
.about h3{font-size:15px;margin:20px 0 6px}
.about ul,.about ol{max-width:70ch;font-size:14px;line-height:1.6;padding-left:22px;margin:0 0 14px}
.about .formula{margin:6px 0 16px}
.about .result{border-left:3px solid var(--color-accent);background:var(--color-surface);padding:8px 12px;margin:0 0 20px}
.about > table.ref{max-width:700px}
.about > table.ref td,.about > table.ref th{vertical-align:top}