:root{--ink:#17212b;--muted:#64717d;--line:#dfe5e9;--paper:#f6f8f8;--card:#fff;--accent:#0d766b;--accent-dark:#075c54;--soft:#eaf5f2;--shadow:0 18px 55px rgba(28,44,51,.10)}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.55}.page-shell{max-width:960px;margin:0 auto;padding:clamp(18px,4vw,52px) 18px 34px}.calculator-card{background:var(--card);border:1px solid var(--line);border-radius:24px;padding:clamp(22px,5vw,48px);box-shadow:var(--shadow)}.eyebrow{font-size:.72rem;letter-spacing:.14em;font-weight:750;color:var(--accent)}h1,h2{line-height:1.12;margin:0}h1{font-size:clamp(2rem,5vw,3.55rem);letter-spacing:-.055em;margin-top:8px}.lede{color:var(--muted);margin:12px 0 28px}.input-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}label span{display:flex;justify-content:space-between;font-weight:700;margin-bottom:7px}label small,.result-tile small{font-weight:500;color:var(--muted)}input{width:100%;border:1px solid #c9d4d7;border-radius:12px;padding:14px 15px;font:inherit;font-size:1.1rem;color:var(--ink);background:#fbfcfc;outline:none}input:focus{border-color:var(--accent);box-shadow:0 0 0 4px rgba(13,118,107,.12)}.primary-button{width:100%;border:0;border-radius:12px;background:var(--accent);color:#fff;font:inherit;font-weight:750;font-size:1rem;padding:15px 18px;margin-top:18px;cursor:pointer}.primary-button:hover{background:var(--accent-dark)}.form-error{color:#a52323;margin:10px 0 0;font-size:.9rem}.results{margin-top:38px;padding-top:28px;border-top:1px solid var(--line)}.results-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:16px}.results-heading h2{font-size:1.35rem;margin-top:5px}.copy-button{border:1px solid #bdd3d0;background:#fff;color:var(--accent-dark);border-radius:10px;padding:9px 12px;font:inherit;font-size:.86rem;font-weight:700;cursor:pointer;white-space:nowrap}.copy-button:hover{background:var(--soft)}.result-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:18px}.result-tile{min-height:142px;border:1px solid var(--line);border-radius:14px;padding:16px;background:#fcfdfd;display:flex;flex-direction:column}.result-tile.featured{background:var(--soft);border-color:#b9ddd7}.result-tile span{font-size:.82rem;color:var(--muted)}.result-tile strong{font-size:clamp(1.35rem,3vw,2rem);letter-spacing:-.04em;margin:10px 0 3px}.result-tile small{font-size:.76rem;line-height:1.35;margin-top:auto}.copy-status{color:var(--accent-dark);font-size:.84rem;min-height:1.2em;margin:10px 0 0}.content-section{padding:46px 10px 0}.content-column{max-width:720px;margin:0 auto}.content-column h2{font-size:1.45rem;margin:0 0 12px}.content-column h2:not(:first-child){margin-top:38px}.content-column p{color:#52606b;margin:0 0 16px}.formula-list{border-left:3px solid var(--accent);margin:20px 0 8px;padding-left:18px;display:grid;gap:13px}.formula-list div{display:flex;gap:16px;justify-content:space-between;align-items:baseline}.formula-list code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--ink);font-size:.9rem}.formula-list span{color:var(--muted);font-size:.85rem;text-align:right}details{border-top:1px solid var(--line);padding:15px 0}details:last-child{border-bottom:1px solid var(--line)}summary{cursor:pointer;font-weight:700}details p{margin:10px 0 0}.page-shell footer{text-align:center;color:var(--muted);font-size:.8rem;margin:32px 0 0}@media(max-width:620px){.page-shell{padding:12px 10px 26px}.calculator-card{border-radius:18px;padding:22px 17px}.input-grid{gap:10px}.result-grid{grid-template-columns:1fr 1fr}.result-tile{min-height:125px}.results-heading{align-items:center}.formula-list div{display:block}.formula-list span{display:block;text-align:left;margin-top:3px}.content-section{padding:34px 4px 0}}