:root{--ink:#111827;--muted:#5f6b7a;--line:#dde3ea;--soft:#f5f7fa;--accent:#f05a0a;--accent-dark:#a6380d;--card:#fff}*{box-sizing:border-box}html{background:#fff}body{margin:0;color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;line-height:1.62;background:linear-gradient(180deg,#fff 0,#fbfcfd 54%,#f7f9fb 100%)}a{color:#2563eb;text-underline-offset:2px}.page-shell{width:min(1120px,calc(100% - 36px));margin:auto}.site-header{padding:28px 0 19px}.brand{display:inline-block;color:#050505;text-decoration:none;font-size:25px;font-weight:950;letter-spacing:-.04em}.crumbs{display:flex;flex-wrap:wrap;gap:7px;align-items:center;margin-top:13px;color:#748091;font-size:13px}.crumbs a{color:#687385;text-decoration:none}.hero{max-width:850px;padding:27px 0 30px}.eyebrow,.panel-kicker{color:var(--accent-dark);font-size:12px;font-weight:850;letter-spacing:.09em;text-transform:uppercase}.hero h1{margin:8px 0 8px;font-size:clamp(36px,5vw,56px);line-height:1.08;letter-spacing:-.045em}.hero p{max-width:760px;margin:0;color:var(--muted);font-size:17px}.tool-layout{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:24px;align-items:start;margin-bottom:44px}.panel{min-width:0;padding:25px;border:1px solid var(--line);border-radius:16px;background:var(--card);box-shadow:0 12px 28px rgba(15,23,42,.055)}.input-panel{border-left:4px solid #ff8b3d}.result-panel{border-top:4px solid var(--accent)}.panel h2{margin:5px 0 18px;font-size:22px}.form-group{min-width:0}.form-group label{display:block;margin-bottom:7px;font-size:14px;font-weight:750}.input-wrap{display:flex;min-width:0;border:1px solid #cfd7e2;border-radius:10px;overflow:hidden;background:#fff}.input-wrap:focus-within{border-color:#ff8b3d;box-shadow:0 0 0 3px rgba(240,90,10,.12)}.input-wrap input{min-width:0;width:100%;padding:12px 13px;border:0;outline:0;font:inherit;color:var(--ink)}.unit-tag{display:flex;align-items:center;padding:0 13px;background:var(--soft);color:#4b5563;border-left:1px solid var(--line);font-weight:700;white-space:nowrap}.hint{margin:7px 0 0;color:#738092;font-size:13px}.actions{display:flex;gap:10px;margin-top:19px}.actions button{border:0;border-radius:9px;padding:12px 18px;font:inherit;font-weight:800;cursor:pointer}.primary{background:var(--accent);color:white}.primary:hover{background:#d94e06}.secondary{background:#f0f2f5;color:#374151}.error{min-height:22px;margin-top:8px;color:#b91c1c;font-size:14px}.answer-label{margin-top:15px;color:#748091;font-size:12px;font-weight:850;letter-spacing:.08em;text-transform:uppercase}.answer{overflow-wrap:anywhere;margin:2px 0 13px;color:var(--accent-dark);font-size:clamp(34px,5vw,49px);font-weight:900;letter-spacing:-.035em}.formula-box{overflow-wrap:anywhere;padding:13px 15px;border-left:3px solid #ff9b57;border-radius:8px;background:#fff6ef;color:#424c59;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:14px}.result-details{margin:16px 0 0;padding-left:20px;color:var(--muted);font-size:14px}.result-details li+li{margin-top:7px}.article{width:min(920px,100%);margin:0 auto 28px}.article.narrow{width:min(810px,100%)}.article.wide{width:100%}.article h2{margin:0 0 9px;font-size:clamp(24px,3vw,31px);line-height:1.2;letter-spacing:-.025em}.article h3{margin:22px 0 7px;font-size:18px}.article p{margin:0 0 13px;color:var(--muted)}.article-card{padding:25px 28px;border:1px solid var(--line);border-radius:14px;background:#fff;box-shadow:0 8px 20px rgba(15,23,42,.035)}.article-accent{padding:23px 27px;border-left:4px solid #ff9b57;background:#fff8f3}.reference-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:11px;margin-top:16px}.reference-item{padding:14px;border:1px solid var(--line);border-radius:10px;background:#fafbfc}.reference-item strong,.reference-item span{display:block}.reference-item span{margin-top:4px;color:var(--muted);overflow-wrap:anywhere}.check-list{margin:8px 0 0;padding-left:21px;color:var(--muted)}.check-list li+li{margin-top:8px}.faq{width:min(920px,100%);margin:40px auto 58px}.faq h2{font-size:28px}.faq details{margin:9px 0;border:1px solid var(--line);border-radius:10px;background:white}.faq summary{padding:15px 17px;cursor:pointer;font-weight:800}.faq details p{padding:0 17px 16px;margin:0;color:var(--muted)}footer{border-top:1px solid var(--line);padding:28px 0 36px;color:#8a94a2;font-size:13px}.footer-links{display:flex;flex-wrap:wrap;justify-content:center;gap:15px}.footer-links a{color:#7c8796;text-decoration:none}@media(max-width:760px){.page-shell{width:min(100% - 20px,1120px)}.site-header{padding-top:18px}.hero{padding-top:18px}.hero h1{font-size:36px}.tool-layout{grid-template-columns:1fr;gap:16px;margin-bottom:35px}.panel{padding:19px}.reference-grid{grid-template-columns:1fr}.article-card,.article-accent{padding:20px}.actions{flex-direction:column}.actions button{width:100%}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}