*{box-sizing:border-box}:root{--bg:#f5f7fa;--surface:#fff;--text:#17212b;--muted:#66727f;--border:#dce2e8;--accent:#2457d6;--accent-soft:#eef3ff;--danger:#b42318;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}body{margin:0;background:var(--bg);color:var(--text);line-height:1.6}button,input,select{font:inherit}a{color:inherit}.container{width:min(1080px,calc(100% - 32px));margin:auto}.site-header{background:#fff;border-bottom:1px solid var(--border)}.site-header-inner{min-height:68px;display:flex;align-items:center;justify-content:space-between}.brand{font-size:1.2rem;font-weight:800;text-decoration:none}.nav{display:flex;gap:24px}.nav a{text-decoration:none;color:var(--muted);font-weight:600}.nav a:hover{color:var(--text)}main{padding:34px 0 72px}.breadcrumbs{display:flex;gap:9px;align-items:center;color:var(--muted);font-size:.88rem;margin-bottom:22px}.breadcrumbs a{text-decoration:none}.page-intro{max-width:760px}.card-kicker,.eyebrow{margin:0 0 4px;color:var(--accent);font-size:.78rem;font-weight:800;text-transform:uppercase;letter-spacing:.08em}.page-intro h1{font-size:clamp(2rem,5vw,3rem);line-height:1.12;margin:0 0 12px}.page-intro>p:last-child{font-size:1.05rem;color:var(--muted);margin:0}.calculator-layout{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(300px,.85fr);grid-gap:20px;gap:20px;margin-top:28px;align-items:stretch}.card{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:26px;box-shadow:0 4px 18px rgba(20,30,40,.04)}.card h2{margin:0}.card-heading{margin-bottom:20px}.mode-list{display:grid;grid-gap:9px;gap:9px;margin-bottom:22px}.mode-option{display:flex;gap:12px;text-align:left;align-items:flex-start;width:100%;padding:13px;border:1px solid var(--border);border-radius:10px;background:#fff;cursor:pointer;color:var(--text)}.mode-option.active,.mode-option:hover{border-color:var(--accent)}.mode-option.active{background:var(--accent-soft)}.mode-option small{display:block;color:var(--muted);margin-top:2px}.mode-radio{width:21px;height:21px;display:grid;place-items:center;border:1px solid #aeb8c4;border-radius:50%;font-size:.75rem;flex:none;margin-top:1px}.active .mode-radio{background:var(--accent);color:#fff;border-color:var(--accent)}.input-grid{display:grid;grid-template-columns:1fr 1fr;grid-gap:14px;gap:14px}.field{display:grid;grid-gap:7px;gap:7px}.field label{font-weight:700}.field input,.field select{width:100%;min-height:48px;border:1px solid var(--border);border-radius:9px;padding:10px 12px;background:#fff}.field input:focus,.field select:focus{outline:3px solid rgba(36,87,214,.16);border-color:var(--accent)}.button-row{display:flex;gap:10px;margin-top:20px}.button{border:0;border-radius:9px;min-height:46px;padding:10px 18px;cursor:pointer;font-weight:800}.button-primary{background:var(--accent);color:#fff}.button-secondary{background:#edf0f3;color:var(--text)}.result-card{background:var(--accent-soft);border-color:#cdd9fa;display:flex;flex-direction:column}.result-label{font-size:.78rem;text-transform:uppercase;letter-spacing:.08em;font-weight:800;color:var(--muted)}.result-empty{margin:auto 0;text-align:center;color:var(--muted)}.result-icon{display:grid;place-items:center;width:58px;height:58px;border-radius:50%;background:#fff;color:var(--accent);font-size:1.5rem;font-weight:800;margin:0 auto 12px}.result-value{font-size:clamp(2.2rem,6vw,3.6rem);line-height:1.1;font-weight:850;margin-top:30px;overflow-wrap:anywhere}.result-note{color:var(--muted);margin-top:8px}.error{color:var(--danger);font-weight:700;margin:14px 0 0}.content-section{max-width:820px;margin-top:42px}.content-section h2{margin-top:34px}.formula{padding:16px 18px;background:#fff;border:1px solid var(--border);border-radius:10px}.related-grid{display:grid;grid-template-columns:repeat(2,1fr);grid-gap:10px;gap:10px}.related-card{padding:14px;background:#fff;border:1px solid var(--border);border-radius:9px;text-decoration:none;font-weight:700}.related-card:hover{border-color:var(--accent)}@media(max-width:760px){.container{width:min(100% - 24px,1080px)}.nav{display:none}.calculator-layout,.input-grid{grid-template-columns:1fr}.card{padding:20px}.result-card{min-height:220px}.related-grid{grid-template-columns:1fr}main{padding-top:24px}}