:root{--bg:#f7f8fb;--card:#fff;--ink:#0f172a;--mut:#5b6476;--line:#e3e7ef;--pri:#2563eb;--pri2:#1d4ed8;--ok:#059669;--bad:#dc2626;--r:14px}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}
body{margin:0;font:16px/1.6 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;background:var(--bg);color:var(--ink)}
a{color:var(--pri)}img{max-width:100%}
.wrap{max-width:960px;margin:0 auto;padding:0 20px}
header.site{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:5}
header.site .wrap{display:flex;align-items:center;gap:20px;height:60px}
.logo{font-weight:800;font-size:1.15rem;color:var(--ink);text-decoration:none;display:flex;align-items:center;gap:8px}
.logo span{background:var(--pri);color:#fff;border-radius:8px;padding:2px 8px;font-size:.9rem}
nav.top{margin-left:auto;display:flex;gap:18px;flex-wrap:wrap}nav.top a{color:var(--mut);text-decoration:none;font-weight:500}nav.top a:hover{color:var(--pri)}
h1{font-size:clamp(1.6rem,4vw,2.3rem);line-height:1.2;margin:28px 0 6px}
.lead{color:var(--mut);margin:0 0 18px;font-size:1.05rem}
.badge{display:inline-flex;align-items:center;gap:6px;background:#ecfdf5;color:var(--ok);border-radius:999px;padding:3px 12px;font-size:.85rem;font-weight:600;margin-bottom:14px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:22px;box-shadow:0 1px 2px rgba(15,23,42,.04)}
.drop{display:block;border:2px dashed #b9c4d8;border-radius:var(--r);padding:38px 16px;text-align:center;cursor:pointer;transition:.15s;background:#fafbff}
.drop.over,.drop:hover{border-color:var(--pri);background:#eff4ff}
.drop strong{display:block;font-size:1.1rem}.drop small{color:var(--mut)}
.drop input{position:absolute;width:1px;height:1px;opacity:0}
.btn{display:inline-block;background:var(--pri);color:#fff;border:0;border-radius:10px;padding:10px 18px;font-weight:600;cursor:pointer;text-decoration:none;font-size:1rem}
.btn:hover{background:var(--pri2)}.btn.small{padding:6px 12px;font-size:.9rem}.btn.ghost{background:#eef2f9;color:var(--ink)}
.row{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-top:14px}
.status{color:var(--mut);font-size:.95rem;margin-top:10px;min-height:1.4em}.status.bad{color:var(--bad)}
ul.results{list-style:none;padding:0;margin:14px 0 0}
ul.results li{display:flex;align-items:center;gap:12px;padding:10px;border:1px solid var(--line);border-radius:10px;margin-bottom:8px;background:#fff}
ul.results li.err{border-color:#fecaca;background:#fef2f2}.thumb{width:48px;height:48px;object-fit:cover;border-radius:6px;background:#eee}
.fname{font-weight:600;word-break:break-all;flex:1}.meta{color:var(--mut);font-size:.9rem}
textarea{width:100%;min-height:220px;font:14px/1.5 ui-monospace,Menlo,Consolas,monospace;border:1px solid var(--line);border-radius:10px;padding:12px;resize:vertical}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:16px}@media(max-width:720px){.grid2{grid-template-columns:1fr}nav.top{gap:12px;font-size:.9rem}}
label.f{font-weight:600;display:block;margin-bottom:6px}
.units{display:grid;grid-template-columns:1fr auto 1fr;gap:12px;align-items:end}.units .eq{font-size:1.6rem;padding-bottom:8px;color:var(--mut)}
.units input{width:100%;font-size:1.6rem;padding:10px 12px;border:1px solid var(--line);border-radius:10px}
.formula{font-family:ui-monospace,monospace;color:var(--mut);margin-top:12px}
section{margin:34px 0}h2{font-size:1.35rem;margin:0 0 10px}
table.ref{border-collapse:collapse;width:100%;background:#fff}table.ref td,table.ref th{border:1px solid var(--line);padding:6px 10px;text-align:left}
details{background:#fff;border:1px solid var(--line);border-radius:10px;padding:12px 16px;margin-bottom:8px}summary{font-weight:600;cursor:pointer}
.links{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:10px}
.links a{display:block;background:#fff;border:1px solid var(--line);border-radius:10px;padding:12px 14px;text-decoration:none;color:var(--ink);font-weight:600}.links a:hover{border-color:var(--pri);color:var(--pri)}
.links a small{display:block;color:var(--mut);font-weight:400}
.hub h2{display:flex;align-items:center;gap:8px}
footer.site{border-top:1px solid var(--line);margin-top:50px;padding:24px 0;color:var(--mut);font-size:.9rem;background:#fff}
footer.site a{color:var(--mut);margin-right:14px}
.hero{padding:30px 0 6px}.hero p{max-width:640px}
select{padding:8px;border-radius:8px;border:1px solid var(--line)}