/* CalcPairs — design system
   Precision instrument: graphite and white, one vivid blue, big tabular
   numerals, flat surfaces, hairline rules. Zero decoration. */
:root{
  --graphite:#14161A; --panel:#1D2026; --panel-2:#24272E;
  --ink:#191B1F; --ink-soft:#33363C; --muted:#62666E; --line:#E3E5E9; --line-dark:#2C2F36;
  --bg:#FFFFFF; --soft:#F5F6F8; --soft-2:#EDEEF1;
  --blue:#2563EB; --blue-deep:#1D4ED8; --blue-soft:#EAF0FE;
  --radius:14px; --shadow:0 10px 30px rgba(20,22,26,.10);
  --num:"Segoe UI",system-ui,-apple-system,Roboto,"Helvetica Neue",Arial,sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:var(--num);
  color:var(--ink);background:var(--bg);font-size:17px;line-height:1.55}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline}
img,svg{max-width:100%}
.tabular{font-variant-numeric:tabular-nums}

/* ---------- header ---------- */
.site-header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50}
.header-in{max-width:1180px;margin:0 auto;padding:10px 18px;display:flex;align-items:center;gap:16px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:11px;color:var(--graphite);font-weight:800;font-size:1.3rem;letter-spacing:-.03em;white-space:nowrap}
.brand:hover{text-decoration:none}
.brand img{width:42px;height:42px;display:block}
.main-nav{display:flex;gap:4px;flex-wrap:wrap;margin-left:auto}
.main-nav a{color:var(--ink);padding:8px 12px;border-radius:999px;font-size:.98rem;font-weight:600}
.main-nav a:hover{background:var(--soft-2);text-decoration:none;color:var(--blue)}

/* ---------- layout ---------- */
.wrap{max-width:1180px;margin:0 auto;padding:0 18px 10px}
.ad-slot{display:flex;align-items:center;justify-content:center;background:var(--soft);border:1px dashed var(--line);
  border-radius:12px;color:var(--muted);font-size:.85rem;min-height:110px;margin:22px 0}

/* ---------- hero / home ---------- */
.hero{background:var(--graphite);color:#fff;border-radius:0 0 22px 22px;margin:0 -18px;padding:46px 34px 42px}
.hero h1{margin:0 0 10px;font-weight:800;font-size:2.35rem;line-height:1.13;letter-spacing:-.025em;max-width:680px;color:#fff}
.hero p{margin:0;color:#C7CAD1;font-size:1.08rem;max-width:680px}
.search-row{display:flex;max-width:560px;background:#fff;border-radius:999px;padding:6px;box-shadow:var(--shadow);margin-top:22px}
.search-row input{flex:1;border:0;outline:0;font-size:1.05rem;padding:10px 16px;color:var(--ink);min-width:0;width:100%;background:transparent}
.cat-block{padding:28px 0 4px}
.cat-block h2{font-size:1.45rem;margin:0 0 16px;color:var(--graphite);letter-spacing:-.015em;font-weight:800}
.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px}
.tool-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:20px 18px;display:block;color:var(--ink);transition:border-color .12s ease,box-shadow .12s ease}
.tool-card:hover{text-decoration:none;box-shadow:var(--shadow);border-color:var(--blue)}
.tool-card .icon{font-size:1.6rem;line-height:1;display:block;margin-bottom:10px}
.tool-card h3{margin:0 0 5px;font-size:1.08rem;color:var(--graphite)}
.tool-card p{margin:0;color:var(--muted);font-size:.94rem}

/* ---------- pair pages ---------- */
.crumbs{font-size:.9rem;color:var(--muted);padding:18px 0 0}
.crumbs a{color:var(--muted)}
main h1{font-weight:800;font-size:2rem;margin:10px 0 8px;color:var(--graphite);letter-spacing:-.02em;line-height:1.2}
.answer-first{background:var(--blue-soft);border:1px solid #CFE0FC;border-left:4px solid var(--blue);
  border-radius:12px;padding:15px 19px;margin:0 0 20px;font-size:1.03rem;color:var(--ink-soft);max-width:880px}

/* the converter instrument */
.conv-card{background:#fff;border:1.5px solid var(--graphite);border-radius:18px;box-shadow:var(--shadow);padding:24px;max-width:880px}
.conv-grid{display:grid;grid-template-columns:1fr auto 1fr;gap:14px;align-items:end}
.conv-grid.h-grid{grid-template-columns:1.15fr auto 1fr 1fr}
.conv-field label{display:block;font-weight:700;margin-bottom:7px;font-size:.92rem;letter-spacing:.05em;text-transform:uppercase;color:var(--muted)}
.conv-field input,.conv-field select{width:100%;padding:14px 15px;font-size:1.55rem;font-weight:700;border:1.5px solid var(--line);border-radius:12px;background:#fff;color:var(--ink);outline:none;font-family:inherit;font-variant-numeric:tabular-nums}
.conv-field select{font-size:1.05rem;font-weight:600;padding:12px 14px}
.conv-field input:focus,.conv-field select:focus{border-color:var(--blue);box-shadow:0 0 0 3px rgba(37,99,235,.18)}
.swap-btn{width:52px;height:52px;border-radius:50%;border:0;background:var(--blue);color:#fff;font-size:1.45rem;line-height:1;cursor:pointer;display:flex;align-items:center;justify-content:center;margin-bottom:2px;box-shadow:0 3px 0 var(--blue-deep)}
.swap-btn:hover{filter:brightness(1.07)}
.swap-btn:active{transform:translateY(2px);box-shadow:0 1px 0 var(--blue-deep)}
.conv-extra{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin-top:16px}
.conv-extra .conv-field input,.conv-extra .conv-field select{font-size:1.05rem}
.conv-readout{margin-top:20px;background:var(--graphite);border-radius:14px;padding:20px 22px;color:#E8EAEE}
.ro-value{display:block;font-size:2.5rem;font-weight:800;color:#fff;line-height:1.16;font-variant-numeric:tabular-nums;letter-spacing:-.015em;word-break:break-word}
.ro-formula{display:block;margin-top:6px;color:#9FB6E8;font-size:1rem;font-variant-numeric:tabular-nums}
.conv-note{color:var(--muted);font-size:.9rem;margin:14px 0 0}

/* ---------- content ---------- */
.expl{max-width:880px;padding:6px 0 4px}
.expl h2{font-size:1.4rem;color:var(--graphite);margin:24px 0 8px;letter-spacing:-.015em;font-weight:800}
.expl p{margin:0 0 12px}
.method{background:var(--soft);border:1px solid var(--line);border-left:4px solid var(--blue);border-radius:12px;padding:16px 20px;margin:20px 0 6px}
.method h3{margin:0 0 6px;font-size:1.05rem;color:var(--graphite)}
.method p{margin:0}
.method .fx{font-size:1.13rem;font-weight:700;color:var(--graphite);font-variant-numeric:tabular-nums}
.disclaimer{border:1px solid var(--line);border-radius:12px;padding:14px 18px;margin:16px 0 6px;color:var(--ink-soft);font-size:.95rem;background:#fff}

/* conversion tables */
.conv-table-wrap{max-width:880px;margin:8px 0 4px}
.conv-table-wrap h2{font-size:1.4rem;color:var(--graphite);margin:24px 0 10px;letter-spacing:-.015em;font-weight:800}
.conv-table{columns:2;column-gap:26px}
.conv-table table{width:100%;border-collapse:collapse;break-inside:avoid;margin:0 0 14px}
.conv-table th,.conv-table td{padding:6px 10px;border-bottom:1px solid var(--line);font-variant-numeric:tabular-nums;font-size:.99rem;text-align:right}
.conv-table th:first-child,.conv-table td:first-child{text-align:left}
.conv-table thead th{background:var(--graphite);color:#fff;font-weight:700;border-bottom:0}
.conv-table tbody tr:nth-child(even){background:var(--soft)}
.tbl-note{color:var(--muted);font-size:.92rem;margin:2px 0 0}
.ref-table{width:100%;max-width:640px;border-collapse:collapse;margin:10px 0 4px}
.ref-table th,.ref-table td{padding:7px 10px;border-bottom:1px solid var(--line);font-variant-numeric:tabular-nums;text-align:right}
.ref-table th:first-child,.ref-table td:first-child{text-align:left}
.ref-table thead th{background:var(--graphite);color:#fff;border-bottom:0}

/* faq / embed / related */
.faq{max-width:880px;margin-top:26px}
.faq h2{font-size:1.4rem;color:var(--graphite);letter-spacing:-.015em;font-weight:800}
.faq details{border:1px solid var(--line);border-radius:12px;padding:13px 17px;margin-bottom:10px;background:#fff}
.faq summary{font-weight:700;cursor:pointer;color:var(--graphite)}
.faq details p{margin:9px 0 2px;color:var(--ink-soft)}
.embed-box{max-width:880px;border:1px solid var(--line);border-radius:14px;padding:20px 22px;margin-top:28px;background:var(--soft)}
.embed-box h2{margin:0 0 8px;font-size:1.25rem;color:var(--graphite)}
.embed-code{background:var(--graphite);color:#D9E4FD;border-radius:10px;padding:13px 15px;overflow-x:auto;font-size:.86rem;white-space:pre-wrap;word-break:break-all}
.embed-credit{color:var(--muted);font-size:.9rem;margin:10px 0 0}
.related{margin-top:30px}
.related h2{font-size:1.4rem;color:var(--graphite);letter-spacing:-.015em;font-weight:800}

/* master converter (home) */
.master{background:#fff;border:1.5px solid var(--graphite);border-radius:18px;box-shadow:var(--shadow);padding:24px;max-width:880px}
.master-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.master .conv-readout{margin-top:18px}

/* static pages */
article.page{max-width:820px}
article.page h1{margin-top:22px}
article.page p{margin:0 0 12px}
.embed-list li{margin-bottom:7px}

/* footer */
.site-footer{background:var(--graphite);color:#C7CAD1;margin-top:52px}
.footer-in{max-width:1180px;margin:0 auto;padding:38px 18px 8px;display:grid;grid-template-columns:1.5fr 1fr 1fr 1.2fr;gap:28px}
.footer-brand{display:flex;align-items:center;gap:10px;color:#fff;font-weight:800;font-size:1.2rem;margin-bottom:10px}
.site-footer p{margin:0;font-size:.95rem}
.site-footer h4{color:#fff;margin:2px 0 10px;font-size:1rem}
.site-footer ul{list-style:none;margin:0;padding:0}
.site-footer li{margin-bottom:7px}
.site-footer a{color:#C7CAD1}
.site-footer a:hover{color:#fff}
.footer-note{max-width:1180px;margin:0 auto;padding:14px 18px 22px;font-size:.88rem;color:#8B8F98;border-top:1px solid var(--line-dark);margin-top:22px}

/* embed pages */
.embed-body{background:#fff}
.embed-wrap{max-width:640px;margin:0 auto;padding:16px}
.embed-h1{font-size:1.3rem;margin:2px 0 14px;color:var(--graphite);font-weight:800;letter-spacing:-.01em}
.embed-wrap .conv-card{box-shadow:none}

@media (max-width:760px){
  .hero{padding:34px 20px 30px}
  .hero h1{font-size:1.72rem}
  main h1{font-size:1.55rem}
  .conv-grid,.conv-grid.h-grid{grid-template-columns:1fr}
  .swap-btn{margin:0 auto}
  .conv-extra,.master-grid{grid-template-columns:1fr}
  .conv-table{columns:1}
  .ro-value{font-size:1.85rem}
  .footer-in{grid-template-columns:1fr 1fr}
  .conv-field input{font-size:1.35rem}
}