:root{--ink:#13253a;--muted:#56677b;--line:#c7d3e0;--brand:#284b91;--soft:#eef4ff;--warn:#8d2b12;font:16px/1.58 system-ui,-apple-system,"Segoe UI",sans-serif;color:var(--ink)}*{box-sizing:border-box}body{margin:0}a{color:#244788}header,footer{display:flex;gap:1.2rem;align-items:center;justify-content:space-between;padding:1rem max(1rem,calc((100% - 1100px)/2));border-bottom:1px solid var(--line)}footer{border-top:1px solid var(--line);border-bottom:0;margin-top:3rem;justify-content:flex-start;flex-wrap:wrap}.brand{font-weight:850;text-decoration:none}nav{display:flex;gap:1rem;flex-wrap:wrap}main{max-width:1100px;margin:auto;padding:1.1rem}.hero{max-width:780px;padding:3rem 0 2rem}.eyebrow{color:var(--brand);font-weight:800;text-transform:uppercase;letter-spacing:.08em}h1{font-size:clamp(2rem,5vw,3.5rem);line-height:1.08;margin:.25rem 0 1rem}.workspace{display:grid;grid-template-columns:minmax(285px,.8fr) minmax(0,1.2fr);gap:1.2rem;align-items:start}form,.result,.content{border:1px solid var(--line);border-radius:14px;padding:1.3rem}label{display:block;font-weight:750;margin-top:.8rem}input[type=number],select{width:100%;padding:.72rem;border:1px solid #7d8da0;border-radius:8px;font:inherit;background:#fff}.check{display:flex;align-items:center;gap:.6rem}.check input{width:auto}.buttons{display:flex;gap:.6rem;flex-wrap:wrap;margin-top:1rem}button{border:0;border-radius:8px;background:var(--brand);color:#fff;padding:.72rem 1rem;font-weight:800;cursor:pointer}.buttons button:nth-child(n+2){background:#dce6fb;color:#17376f}.result{background:var(--soft)}#status{font-size:1.6rem}.error{color:var(--warn);font-weight:700}.content{max-width:850px;margin-top:1.5rem}.feature-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:.8rem}.feature-grid div{background:#f5f7fa;padding:1rem;border-left:4px solid var(--brand)}:focus-visible{outline:3px solid #c56200;outline-offset:3px}@media(max-width:760px){header{align-items:flex-start;flex-direction:column}.workspace,.feature-grid{grid-template-columns:1fr}main{padding:1rem}}