:root{--leaf:#164b35;--leaf2:#28734f;--tape:#ffd447;--water:#1387a8;--paper:#f5f7ef;--ink:#172019;--muted:#5d695f;--line:#b8c5b8;--max:1180px}*{box-sizing:border-box}html{scroll-behavior:smooth}body{background:var(--paper);color:var(--ink);background-image:linear-gradient(#d9e0d433 1px,#0000 1px),linear-gradient(90deg,#d9e0d433 1px,#0000 1px);background-size:32px 32px;margin:0;font-family:system-ui,-apple-system,Segoe UI,sans-serif;font-size:18px;line-height:1.55}a{color:var(--leaf);text-underline-offset:4px}a:hover{text-decoration-thickness:3px}.skip{position:absolute;left:-999px}.skip:focus{z-index:10;background:#fff;padding:.7rem;top:1rem;left:1rem}header,footer,main{max-width:var(--max);margin:auto}header{border-bottom:3px solid var(--leaf);justify-content:space-between;align-items:center;padding:1rem 1.25rem;display:flex}.brand{align-items:center;gap:.75rem;font-family:Arial Narrow,Aptos Narrow,Impact,sans-serif;font-size:1.25rem;line-height:1;text-decoration:none;display:flex}.brand small{color:var(--muted);font:600 .75rem system-ui,-apple-system,Segoe UI,sans-serif}.brand-mark{background:var(--tape);color:var(--ink);padding:.65rem .4rem;font-weight:800;transform:rotate(-2deg)}nav{flex-wrap:wrap;gap:1.2rem;display:flex}nav a{font-weight:700;text-decoration:none}main{min-height:70vh}.hero{grid-template-columns:minmax(0,1.5fr) minmax(260px,.7fr);align-items:end;gap:3rem;padding:5rem 1.25rem 3rem;display:grid}.kicker{color:var(--leaf2);margin:0 0 .6rem;font-weight:700}.hero h1,.page-head h1{letter-spacing:-.035em;max-width:900px;margin:0;font:800 clamp(3rem,8vw,6.5rem)/.88 Arial Narrow,Aptos Narrow,Impact,sans-serif}.hero h1{font-size:clamp(3.8rem,9vw,7.2rem)}.lead{max-width:720px;font-size:1.3rem}.measure{border-left:16px solid var(--tape);background:#fff;border-radius:0 16px 16px 0;padding:1.25rem 1.5rem;box-shadow:8px 8px #164b3522}.measure strong{font:800 3.2rem Arial Narrow,Aptos Narrow,Impact,sans-serif;display:block}.btn{background:var(--leaf);color:#fff;border:2px solid var(--leaf);padding:.8rem 1.1rem;font-weight:700;text-decoration:none;display:inline-block}.btn.alt{color:var(--leaf);background:0 0}.actions{flex-wrap:wrap;gap:.8rem;display:flex}.section{padding:3rem 1.25rem}.section h2,.content h2{margin:0 0 1.3rem;font:800 2.35rem/1 Arial Narrow,Aptos Narrow,Impact,sans-serif}.grid{grid-template-columns:repeat(3,1fr);gap:1rem;display:grid}.card{border:1px solid var(--line);border-top:7px solid var(--leaf);background:#fff;padding:1.3rem}.card h2,.card h3{margin:.2rem 0 .6rem;font:700 1.55rem/1.1 Arial Narrow,Aptos Narrow,Impact,sans-serif}.card p{color:var(--muted)}.page-head{border-bottom:1px solid var(--line);padding:4rem 1.25rem 2rem}.content{max-width:820px;margin-left:clamp(0px,8vw,110px);padding:2rem 1.25rem 5rem}.toc{border-left:10px solid var(--tape);background:#fff;margin:1.5rem 0;padding:1rem 1.4rem}.toc a{display:block}.steps li{margin:.8rem 0}.note{border-left:8px solid var(--water);background:#e5f4f7;padding:1rem 1.2rem}.source{color:var(--muted);font-size:.95rem}footer{border-top:3px solid var(--leaf);background:#edf1e7;padding:2.5rem 1.25rem 4rem}.calculator{grid-template-columns:1fr 1fr;align-items:start;gap:2rem;display:grid}.panel{border:1px solid var(--line);background:#fff;padding:1.5rem}.field{gap:.35rem;margin-bottom:1rem;display:grid}label{font-weight:700}input,select{font:inherit;background:#fff;border:2px solid #718078;width:100%;padding:.65rem}button{background:var(--leaf);color:#fff;cursor:pointer;border:0;padding:.85rem 1.2rem;font:700 1rem system-ui,-apple-system,Segoe UI,sans-serif}.result{border-left:14px solid var(--tape);min-height:220px}.result output{font:800 2.7rem Arial Narrow,Aptos Narrow,Impact,sans-serif;display:block}.formula{background:#edf1e7;padding:.8rem;font-family:ui-monospace,monospace;font-size:.9rem;overflow:auto}.tool-list{columns:2;column-gap:2rem}.tool-list li{break-inside:avoid;margin-bottom:.7rem}@media (width<=760px){body{font-size:17px}header{align-items:flex-start;gap:1rem}header nav{gap:.65rem;font-size:.9rem}.hero,.calculator{grid-template-columns:1fr}.hero{padding-top:3rem}.grid{grid-template-columns:1fr}.content{margin:0}.tool-list{columns:1}}@media print{header,footer,.actions,button,.skip{display:none}body{background:#fff}.panel{break-inside:avoid}}.breadcrumbs{border-bottom:1px solid #b8c5b8;max-width:1180px;margin:0 auto;padding:.8rem 1.25rem;font-size:.9rem}table{border-collapse:collapse;background:#fff;width:100%}th,td{text-align:left;vertical-align:top;border:1px solid #b8c5b8;padding:.7rem}dt{margin-top:1rem;font-weight:800}dd{color:#5d695f;margin-left:0}:focus-visible{outline-offset:3px;outline:4px solid #1387a8}@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}.page-head,.toc{display:block}html,body{overflow-x:hidden}@media (width<=760px){body>header{display:block}body>header nav{margin-top:1rem}.page-head h1{font-size:3.4rem}.page-head .lead{font-size:1.1rem}}