:root{
  --bg:#f7f9fc; --card:#ffffff; --text:#0f172a; --muted:#475569;
  --accent:#2563eb; --accent2:#22c55e; --border:#e5e7eb;
  --radius:16px; --font: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
}
*{box-sizing:border-box}
body{margin:0;font-family:var(--font);background:var(--bg);color:var(--text)}
.container{max-width:1100px;margin:0 auto;padding:0 18px 64px}
a{color:var(--accent);text-decoration:none}
.nav{display:flex;justify-content:space-between;align-items:center;padding:18px 0}
.brand{font-weight:900;font-size:20px;color:var(--text)}
.nav a{margin-left:14px;font-size:14px;color:var(--muted)}
.hero{padding:24px 0}
.hero h1{margin:0;font-size:clamp(30px,4vw,44px);line-height:1.1}
.hero p{margin-top:12px;max-width:70ch;color:var(--muted);line-height:1.7}
.grid{display:grid;grid-template-columns:1fr;gap:20px}
.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:20px}
label{display:block;font-size:13px;color:var(--muted);margin-bottom:6px}
input,select{width:100%;padding:14px;border-radius:12px;border:1px solid var(--border);font-size:16px}
button{padding:14px;border-radius:12px;border:none;background:var(--accent);color:#fff;font-weight:800;font-size:16px;cursor:pointer}
button.secondary{background:#e5e7eb;color:#111}
.calc{display:grid;grid-template-columns:1fr 1fr;gap:16px}
@media(max-width:800px){.calc{grid-template-columns:1fr}}
.results{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:16px}
@media(max-width:800px){.results{grid-template-columns:1fr}}
.stat{padding:16px;border-radius:14px;background:#f8fafc;border:1px solid var(--border)}
.big{font-size:28px;font-weight:900}
.footer{margin-top:40px;font-size:12px;color:var(--muted)}