:root{--bg:#f4f6f9;--card:#fff;--ink:#1d2733;--muted:#5f6b7a;--line:#dfe4ea;--brand:#1a56a8;--brand-d:#123f7d;--brand-l:#e8f0fb;--accent:#f2a900;--ok:#1e7b46;--err:#b42318;--soft:#f7f9fc}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.6 "Source Sans 3",system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif}
a{color:var(--brand)}
.wrap{max-width:1120px;margin:0 auto;padding:0 16px}
.ico{flex:none}
/* header */
header.top{background:var(--brand);color:#fff}
header.top .wrap{display:flex;align-items:center;gap:16px;min-height:58px}
.logo{display:flex;align-items:center;gap:10px;font-weight:700;font-size:21px;color:#fff;text-decoration:none;letter-spacing:-.2px}
.logo svg{width:32px;height:32px;flex:none;border-radius:8px;box-shadow:0 0 0 2px rgba(255,255,255,.25)}
nav.main{display:flex;gap:2px;margin-left:auto;flex-wrap:wrap}
nav.main a{padding:7px 11px;border-radius:6px;color:#fff;text-decoration:none;font-weight:600;font-size:15px;opacity:.92}
nav.main a:hover{background:rgba(255,255,255,.14);opacity:1}
.inst{display:flex;align-items:center;gap:6px;padding:7px 12px;border-radius:6px;border:1px solid rgba(255,255,255,.55);background:transparent;color:#fff;font:inherit;font-weight:600;font-size:14px;cursor:pointer}
.inst:hover{background:rgba(255,255,255,.14)}
.lang{position:relative}
.lang summary{list-style:none;cursor:pointer;display:flex;align-items:center;gap:6px;padding:7px 10px;border-radius:6px;font-weight:700;font-size:14px;color:#fff}
.lang summary:hover{background:rgba(255,255,255,.14)}
.lang summary::-webkit-details-marker{display:none}
.lang div{position:absolute;right:0;top:42px;z-index:30;background:#fff;border:1px solid var(--line);border-radius:8px;box-shadow:0 8px 24px rgba(20,30,50,.15);padding:6px;min-width:150px}
.lang a{display:block;padding:8px 10px;border-radius:6px;color:var(--ink);text-decoration:none;font-size:15px}
.lang a:hover,.lang a[aria-current]{background:var(--brand-l)}
@media(max-width:820px){nav.main{display:none}.lang{margin-left:auto}.inst span{display:none}}
/* home */
.hero{background:linear-gradient(180deg,var(--brand-l),var(--bg));border-bottom:1px solid var(--line);padding:34px 0 30px}
.hero .wrap{display:grid;grid-template-columns:1.2fr 1fr;gap:28px;align-items:center}
.hero h1{font-size:clamp(28px,4vw,40px);line-height:1.15;margin:0 0 8px;letter-spacing:-.4px}
.hero p{color:var(--muted);font-size:17.5px;margin:0}
@media(max-width:820px){.hero .wrap{grid-template-columns:1fr}}
.search input{width:100%;padding:14px 16px;border:1px solid #c8d1dc;border-radius:8px;font:inherit;font-size:17px;background:#fff;color:var(--ink);outline:0;box-shadow:0 1px 2px rgba(20,30,50,.06)}
.search input:focus{border-color:var(--brand);box-shadow:0 0 0 3px rgba(26,86,168,.15)}
h2.sec{font-size:21px;margin:30px 0 12px}
.tiles{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:12px}
.tile{display:flex;gap:12px;align-items:flex-start;background:var(--card);border:1px solid var(--line);border-radius:8px;padding:14px;text-decoration:none;color:var(--ink)}
.tile:hover{border-color:var(--brand)}
.tile .ic{width:42px;height:42px;border-radius:8px;background:var(--brand-l);color:var(--brand);display:grid;place-items:center;flex:none}
.tile b{display:block;font-size:16.5px;line-height:1.3}.tile small{color:var(--muted);font-size:14px;line-height:1.35;display:block;margin-top:2px}
.cats{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:12px}
.catcol{background:var(--card);border:1px solid var(--line);border-radius:8px;padding:16px 18px}
.catcol h2{display:flex;align-items:center;gap:8px;font-size:18px;margin:0 0 8px;color:var(--brand-d)}
.catcol ul{list-style:none;margin:0;padding:0}
.catcol li a{display:block;padding:5px 0;text-decoration:none;color:var(--brand);font-size:16px;border-bottom:1px solid #eef1f5}
.catcol li:last-child a{border-bottom:0}
.catcol li a:hover{text-decoration:underline}
.aboutbox{margin:30px 0 0;padding:18px 20px;background:var(--card);border:1px solid var(--line);border-radius:8px}
.aboutbox h2{font-size:18px;margin:0 0 6px}.aboutbox p{margin:0;color:var(--muted)}
/* calculator page */
.crumbs{font-size:14px;color:var(--muted);margin:18px 0 6px}
.crumbs a{color:var(--muted);text-decoration:none}.crumbs a:hover{color:var(--brand)}
h1{font-size:clamp(26px,3.6vw,34px);line-height:1.2;margin:4px 0 6px;letter-spacing:-.3px}
h1.ch{display:flex;align-items:center;gap:12px}
.chi{width:48px;height:48px;border-radius:10px;background:var(--brand-l);color:var(--brand);display:grid;place-items:center;flex:none}
.by{font-size:14px;color:var(--muted);margin:0 0 10px}
.lead{color:var(--muted);font-size:17.5px;margin:0 0 18px;max-width:760px}
.grid{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:24px;align-items:start}
@media(max-width:960px){.grid{grid-template-columns:1fr}}
.card{background:var(--card);border:1px solid var(--line);border-radius:8px;padding:20px}
#calc{display:grid;grid-template-columns:1fr 1fr;gap:22px}
@media(max-width:760px){#calc{grid-template-columns:1fr}}
#cf{display:flex;flex-wrap:wrap;gap:12px;align-content:start}
.f{display:block;width:100%}.f.half{width:calc(50% - 6px)}
@media(max-width:420px){.f.half{width:100%}}
.f>span{display:block;font-size:14.5px;font-weight:600;color:var(--ink);margin-bottom:4px}
.in{display:flex;align-items:center;border:1px solid #c8d1dc;border-radius:6px;background:#fff;overflow:hidden}
.in:focus-within{border-color:var(--brand);box-shadow:0 0 0 3px rgba(26,86,168,.15)}
.in input,.in select{flex:1;min-width:0;border:0;background:transparent;color:var(--ink);font:inherit;font-size:16.5px;padding:10px 12px;outline:0}
.in select{cursor:pointer}
.in.has-sel select{flex:none;width:auto;max-width:52%;border-left:1px solid var(--line);font-size:14.5px;font-weight:600;color:var(--muted);padding:10px 8px;background:var(--soft)}
.pre,.suf{padding:0 10px;color:var(--muted);font-weight:600;font-size:15px;white-space:nowrap}
.pre{padding-right:0}.suf{padding-left:0}
details.more{width:100%;border:1px dashed #c8d1dc;border-radius:6px;padding:8px 12px}
details.more summary{cursor:pointer;font-weight:600;font-size:15px;color:var(--brand)}
details.more[open]{display:flex;flex-wrap:wrap;gap:12px}
details.more[open] summary{width:100%}
.chk{display:flex;gap:8px;align-items:center;font-size:15px;width:100%}
.btns{display:flex;gap:10px;width:100%;margin-top:4px}
.go{flex:1;padding:12px;border:0;border-radius:6px;background:var(--ok);color:#fff;font:inherit;font-weight:700;font-size:17px;cursor:pointer}
.go:hover{background:#17663a}
.rs{padding:12px 16px;border:1px solid #c8d1dc;border-radius:6px;background:#fff;color:var(--muted);font:inherit;font-weight:600;cursor:pointer}
#out{min-width:0}
.big{background:var(--brand-l);border-left:4px solid var(--brand);border-radius:6px;padding:14px 16px;margin-bottom:10px;color:var(--ink)}
.big small{display:block;color:var(--brand-d);font-weight:700;font-size:14.5px}
.big b{display:block;font-size:clamp(26px,3.6vw,32px);line-height:1.15;margin:2px 0;font-variant-numeric:tabular-nums;color:var(--brand-d)}
.big em{font-style:normal;color:var(--muted);font-size:14.5px}
.kv{display:flex;justify-content:space-between;gap:12px;padding:8px 2px;border-bottom:1px solid var(--line);font-size:15.5px}
.kv span{color:var(--muted)}.kv b{text-align:right;font-variant-numeric:tabular-nums;font-weight:600}
.err{color:var(--err);font-weight:600}.ok{color:var(--ok);font-weight:700}
.split{margin:14px 0 6px}
.bar{display:flex;height:12px;border-radius:3px;overflow:hidden;background:var(--line)}
.bar i,.lg i{background:var(--brand)}.bar u,.lg u{background:var(--accent)}
.bar i,.bar u{display:block;height:100%}
.lg{display:flex;gap:16px;flex-wrap:wrap;font-size:14px;color:var(--muted);margin-top:6px}
.lg span{display:flex;align-items:center;gap:6px}.lg i,.lg u{display:inline-block;width:12px;height:12px;border-radius:2px}
.cols{display:flex;align-items:flex-end;gap:2px;height:140px;margin:14px 0 4px;padding-top:6px;border-bottom:1px solid var(--line)}
.cols div{flex:1;display:flex;flex-direction:column-reverse;height:100%}
.cols i{display:block;background:var(--brand)}.cols u{display:block;background:var(--accent)}
.tgl{margin-top:12px;background:#fff;border:1px solid #c8d1dc;border-radius:6px;padding:7px 12px;color:var(--brand);font:inherit;font-weight:600;font-size:15px;cursor:pointer}
.tbl{max-height:360px;overflow:auto;margin-top:10px;border:1px solid var(--line);border-radius:6px}
table{width:100%;border-collapse:collapse;font-size:15px;font-variant-numeric:tabular-nums}
th,td{padding:7px 10px;text-align:right;border-bottom:1px solid var(--line);white-space:nowrap}
th:first-child,td:first-child{text-align:left}
th{position:sticky;top:0;background:var(--soft);font-size:14px}
article table td,article table th{white-space:normal}
.tag{display:inline-block;padding:1px 10px;border-radius:999px;font-weight:700;font-size:13.5px;background:#fff;color:#111}
.tag.c1{background:#d6e6ff}.tag.c2{background:#d3f0dd}.tag.c3{background:#ffe8b8}.tag.c4{background:#ffd3d0}
.gauge{position:relative;margin:16px 0 8px}
.gauge div{display:flex;height:12px;border-radius:3px;overflow:hidden}
.gauge i{display:block;height:100%}
.gauge .c1{background:#6aa8ff;width:14%}.gauge .c2{background:#2fa463;width:26%}.gauge .c3{background:#f2a900;width:20%}.gauge .c4{background:#d9534f;width:40%}
.gauge b{position:absolute;top:-5px;width:4px;height:22px;background:var(--ink);border-radius:2px;transform:translateX(-50%)}
.gauge small{display:flex;justify-content:space-between;font-size:12px;color:var(--muted);margin-top:4px}
.pct{width:100%;display:grid;gap:14px}
.pr{border:1px solid var(--line);border-radius:6px;padding:12px}
.pr>b{display:block;margin-bottom:8px}
.pr .line{display:flex;align-items:flex-end;gap:8px;flex-wrap:wrap}
.pr .line .f{width:auto;flex:1;min-width:90px}
.pr .line>span{padding-bottom:10px;color:var(--muted);font-weight:700}
.pr output{min-width:110px;padding:10px 12px;border-radius:6px;background:var(--brand-l);font-weight:700;color:var(--brand-d);font-variant-numeric:tabular-nums}
#calc:has(.pct){grid-template-columns:1fr}
/* share */
.share{display:flex;flex-wrap:wrap;align-items:center;gap:8px;margin:12px 0 0;font-size:15px}
.share>span{color:var(--muted);font-weight:600;margin-right:4px}
.share button{display:inline-flex;align-items:center;gap:6px;padding:7px 11px;border:1px solid #c8d1dc;border-radius:6px;background:#fff;color:var(--ink);font:inherit;font-size:14.5px;font-weight:600;cursor:pointer}
.share button:hover{border-color:var(--brand);color:var(--brand)}
.share .wa{background:#1f9d55;border-color:#1f9d55;color:#fff}.share .wa:hover{background:#178246;color:#fff}
/* article */
article{margin-top:26px}
article h2{font-size:23px;margin:30px 0 8px}
article h3{font-size:18px;margin:20px 0 6px}
article .formula{background:var(--soft);border:1px solid var(--line);border-radius:6px;padding:12px 14px;font-family:ui-monospace,Consolas,monospace;font-size:15px;overflow-x:auto}
.faq details{border:1px solid var(--line);border-radius:6px;padding:11px 14px;margin:8px 0;background:var(--card)}
.faq summary{cursor:pointer;font-weight:600}
.note{font-size:14px;color:var(--muted);border-left:3px solid var(--line);padding-left:12px;margin-top:22px}
/* sidebar */
aside.side .card{padding:14px 16px}
aside.side h3{font-size:16px;margin:0 0 6px}
aside.side ul{list-style:none;margin:0;padding:0}
aside.side li a{display:flex;gap:10px;align-items:center;padding:7px 4px;color:var(--brand);text-decoration:none;font-size:15.5px;border-bottom:1px solid #eef1f5}
aside.side li:last-child a{border-bottom:0}
aside.side li a:hover{text-decoration:underline}
aside.side li .ico{color:var(--muted)}
/* plain pages */
.page{max-width:800px}
.page h2{font-size:21px;margin-top:26px}
/* footer */
footer{margin-top:50px;background:#1d2733;color:#c9d2dd;padding:30px 0 20px;font-size:15px}
.fcols{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:20px}
.fcols b{display:block;color:#fff;margin-bottom:6px}
.fcols a{display:block;color:#c9d2dd;text-decoration:none;padding:2px 0;font-size:14.5px}
.fcols a:hover{color:#fff;text-decoration:underline}
.fnote{margin:24px 0 0;padding-top:14px;border-top:1px solid #34404e;font-size:13.5px;color:#9aa6b4}
.grp{display:contents}.grp[hidden]{display:none}
.chart{margin:14px 0 4px}.chart figcaption{font-size:14px;font-weight:600;color:var(--muted);margin-bottom:4px}
.chart svg{width:100%;height:auto;display:block}.chart .ax{stroke:#c8d1dc;stroke-width:1}.chart .ln{fill:none;stroke:var(--brand);stroke-width:2.2}
.chart .ar{fill:var(--brand-l)}.chart text{font-size:10px;fill:var(--muted)}
.seealso{margin-top:28px}.seealso h2{font-size:21px;margin:0 0 10px}
.src{font-size:13.5px;color:var(--muted);margin:2px 0 0;width:100%}
.embedbox{margin:28px 0;padding:18px;border:1px solid var(--line,#dde3ea);border-radius:10px;background:#fafbfd}
.embedbox h2{margin-top:0}
.embedbox textarea{width:100%;box-sizing:border-box;font:12.5px/1.45 ui-monospace,Consolas,monospace;padding:10px;border:1px solid var(--line,#dde3ea);border-radius:8px;background:#fff;resize:vertical;color:#333}
.embedbox .btn{margin-top:8px}
body.embed{background:transparent;margin:0;padding:8px}
body.embed .card{margin:0}
.eh{display:flex;align-items:center;gap:8px;font-size:19px;margin:0 0 12px}
.ef{text-align:right;font-size:13px;margin:6px 4px 0}.ef a{color:var(--muted,#667);text-decoration:none}
.btn{display:inline-block;background:#1a56a8;color:#fff;border:0;border-radius:8px;padding:9px 16px;font:600 15px/1.2 inherit;font-family:inherit;cursor:pointer}.btn:hover{background:#15488d}