:root{--ink:#17324d;--tape:#f5b800;--bg:#f3f5f7;--txt:#26333e;--mut:#56646f;--line:#d3dbe2}
*{box-sizing:border-box}
body{margin:0;font:17px/1.65 "Segoe UI",system-ui,-apple-system,Roboto,sans-serif;color:var(--txt);background:var(--bg)}
a{color:#0b5394}a:hover{color:#8a5a00}
.top{background:var(--ink);background-image:linear-gradient(rgba(255,255,255,.06) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.06) 1px,transparent 1px);background-size:24px 24px;border-bottom:4px solid var(--tape)}
.in{max-width:980px;margin:auto;padding:16px 20px;display:flex;flex-wrap:wrap;gap:8px 28px;align-items:center;justify-content:space-between}
.logo{font-weight:800;font-size:1.3rem;letter-spacing:-.01em;color:#fff;text-decoration:none}
.top nav a{color:#d9e4ee;text-decoration:none;margin-right:18px;font-size:.95rem}
.top nav a:hover,.top nav a:focus{color:var(--tape)}
.wrap{max-width:980px;margin:auto;padding:28px 20px 48px}
h1,h2,h3{line-height:1.2;color:var(--ink);letter-spacing:-.015em}
h1{font-size:2.2rem;font-weight:800;margin:.2em 0 .3em}
h2{font-size:1.5rem;font-weight:700;margin:2em 0 .4em}
h3{font-size:1.1rem;margin:1.3em 0 .2em}
p{max-width:72ch}
.lead{font-size:1.15rem;color:var(--mut)}
.panel{background:#fff;border:1px solid var(--line);border-radius:4px;padding:22px;margin:22px 0}
.calc{border-top:0;padding-top:34px;position:relative;display:grid;grid-template-columns:repeat(auto-fit,minmax(190px,1fr));gap:16px}
.calc:before,.result:before{content:"";position:absolute;left:0;right:0;top:0;height:14px;background:repeating-linear-gradient(90deg,var(--ink) 0 2px,transparent 2px 10px),repeating-linear-gradient(90deg,var(--ink) 0 2px,transparent 2px 50px);background-size:10px 8px,50px 14px;background-repeat:repeat-x;background-color:var(--tape)}
.result{position:relative;padding-top:34px}
label{display:flex;flex-direction:column;font-size:.9rem;font-weight:600;gap:4px}
input[type=number]{padding:10px;border:1px solid #aab7c2;border-radius:3px;font:inherit;width:100%}
input:focus,button:focus,a:focus{outline:3px solid #0b5394;outline-offset:2px}
label.chk{flex-direction:row;align-items:center;gap:8px;align-self:end}
button{grid-column:1/-1;justify-self:start;background:var(--tape);color:#1b1b1b;border:0;border-radius:3px;padding:12px 28px;font:inherit;font-weight:800;cursor:pointer}
button:hover{background:#ffcb2e}
.big{font-size:2.4rem;font-weight:800;color:var(--ink);font-variant-numeric:tabular-nums}
.result ul{margin:.4em 0 0;padding-left:1.2em;font-variant-numeric:tabular-nums}
.tw{overflow-x:auto}
table{border-collapse:collapse;width:100%;margin:12px 0;font-variant-numeric:tabular-nums}
th,td{border:1px solid var(--line);padding:8px 12px;text-align:left}
th{background:#e8edf2}
.tools{list-style:none;margin:20px 0;padding:0;border-top:2px solid var(--ink)}
.tools li{border-bottom:1px solid var(--line)}
.tools a{display:grid;grid-template-columns:minmax(150px,220px) 1fr;gap:4px 24px;padding:16px 4px;text-decoration:none;color:var(--txt)}
.tools a:hover{background:#fff}
.tools b{color:var(--ink);font-size:1.15rem}
@media(max-width:600px){.tools a{grid-template-columns:1fr}h1{font-size:1.8rem}}
.note{font-size:.9rem;color:var(--mut)}
footer{background:var(--ink);color:#c5d3df;font-size:.92rem}
footer a{color:#fff;margin-right:16px}
.post{max-width:72ch}
.post p,.post li{font-size:1.1rem;line-height:1.8}
.post h2{margin-top:2.4em}
.post h2:before{content:"";display:block;width:44px;height:4px;background:var(--tape);margin-bottom:12px}
.crumb{font-size:.9rem;margin:0}
.meta{color:var(--mut);font-size:.92rem;margin-top:-.3em}
.toc{background:#fff;border:1px solid var(--line);border-left:4px solid var(--ink);padding:14px 22px;margin:24px 0}
.toc ol{margin:.4em 0 0;padding-left:1.3em}
.toc a{text-decoration:none}
.tip{background:#fff6d6;border-left:4px solid var(--tape);padding:12px 18px;margin:22px 0}
.cta{background:var(--ink);color:#fff;padding:24px;margin:40px 0;border-radius:4px}
.cta b{font-size:1.25rem}.cta p{color:#d9e4ee;margin:.3em 0 1em}
.cta a{display:inline-block;background:var(--tape);color:#1b1b1b;font-weight:800;padding:10px 24px;border-radius:3px;text-decoration:none}