:root{color-scheme:light;--bg:#f4f6fa;--surface:#fff;--surface-2:#edf1f7;--ink:#162536;--muted:#596778;--line:#d7dfe9;--brand:#3153d8;--brand-hover:#2041c0;--brand-soft:#e9edff;--accent:#d8f78c;--danger:#a02232;--shadow:0 12px 40px #172a4410;--radius:18px;--mono:ui-monospace,SFMono-Regular,Consolas,monospace}
:root[data-theme=dark]{color-scheme:dark;--bg:#101824;--surface:#182433;--surface-2:#202e40;--ink:#f0f4fa;--muted:#aab9cb;--line:#354456;--brand:#a9baff;--brand-hover:#c3d0ff;--brand-soft:#29375c;--accent:#d8f78c;--danger:#ffabb5;--shadow:0 12px 40px #0003}
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3px;background-position:bottom;background-repeat:no-repeat}.nav-links{display:flex;align-items:center;gap:23px;margin-left:auto}.nav-links>a{color:var(--muted);font-size:14px;font-weight:650;text-decoration:none}.nav-links>a[aria-current=page]{color:var(--ink)}.nav-actions{display:flex;gap:12px;align-items:center}.language{font-size:14px;font-weight:650;text-decoration:none;white-space:nowrap}.theme-button{width:36px;height:36px;background:var(--surface-2);border:1px solid var(--line);color:var(--ink);border-radius:50%;line-height:1;font-size:21px}.container{max-width:1280px;margin:auto;padding:0 28px}.home-intro{padding:58px 0 28px;display:flex;justify-content:space-between;align-items:end;gap:40px}.eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:1.8px;text-transform:uppercase;color:var(--muted);font-weight:650}.eyebrow:before{content:"";display:inline-block;width:7px;height:7px;background:var(--brand);margin-right:9px;border-radius:50%}h1,h2,h3,p{margin-top:0}h1{font-size:clamp(32px,4vw,52px);line-height:1.1;letter-spacing:-1.8px;margin-bottom:16px;max-width:750px}h2{font-size:clamp(23px,2.2vw,31px);line-height:1.22;letter-spacing:-.8px}h3{font-size:20px;line-height:1.3;letter-spacing:-.4px}.lede{font-size:18px;line-height:1.6;max-width:680px;color:var(--muted);margin-bottom:0}.home-note{border-left:2px solid var(--line);padding-left:20px;font-size:14px;color:var(--muted);max-width:215px;flex-shrink:0}.tool-cards{display:grid;grid-template-columns:1fr 1fr;gap:22px}.tool-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:30px;text-decoration:none;color:var(--ink);display:grid;grid-template-columns:1.15fr .85fr;gap:22px;min-height:320px;box-shadow:var(--shadow);overflow:hidden}.tool-card:hover{border-color:var(--brand);transform:translateY(-2px)}.tool-card .small-tag{display:inline-block;background:var(--brand-soft);color:var(--brand);padding:3px 9px;border-radius:6px;font-size:12px;font-weight:750;margin-bottom:24px}.tool-card h2{font-size:29px;max-width:300px}.tool-card p{color:var(--muted);font-size:15px}.link-arrow{display:block;font-size:15px;font-weight:750;color:var(--brand);margin-top:25px}.paper-diagram{position:relative;align-self:center;width:100%;aspect-ratio:210/297;background:#fff;border:1px solid #c8d0db;border-radius:2px;box-shadow:5px 7px 0 var(--surface-2);display:grid;grid-template-columns:repeat(2,1fr);gap:7px;padding:22px 13px}.paper-diagram span{background:#e7ecff;border:1px solid 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0;line-height:1.5}.inline-button{border:0;background:none;padding:0;color:var(--brand);text-decoration:underline;text-underline-offset:3px;font-size:13px;font-weight:650;margin-top:12px}.button{display:inline-flex;justify-content:center;align-items:center;gap:12px;background:var(--brand);color:white;border:0;padding:13px 20px;min-height:48px;border-radius:9px;font-size:15px;font-weight:750;text-decoration:none}.button:hover{background:var(--brand-hover)}[data-theme=dark] .button{color:#142037}.button.full{width:100%}.preview-panel{background:var(--surface-2);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden}.preview-header{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:16px 22px;background:var(--surface);border-bottom:1px solid 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@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.tool-card:hover{transform:none}}

.invalid-result .calc-stats,.invalid-result .formula-note{opacity:.55}.button[aria-disabled="true"]{opacity:.45;cursor:not-allowed}