/* KiraCalc design system — single stylesheet, no framework. */
:root{
  --bg:#f6f8f7; --card:#ffffff; --ink:#15201c; --muted:#5b6b64;
  --brand:#1f9d72; --brand-d:#177a59; --line:#e3e9e6; --accent:#eef7f3;
  --radius:14px; --shadow:0 1px 2px rgba(16,40,32,.06),0 6px 18px rgba(16,40,32,.06);
  --maxw:1060px; --font:system-ui,-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:var(--font);color:var(--ink);background:var(--bg);line-height:1.6;-webkit-font-smoothing:antialiased}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 18px}
a{color:var(--brand-d);text-decoration:none}
a:hover{text-decoration:underline}
h1,h2,h3,h4{line-height:1.25;margin:0 0 .5em}
h1{font-size:1.9rem}h2{font-size:1.35rem;margin-top:1.6em}h3{font-size:1.1rem;margin-top:1.3em}
p{margin:0 0 1em}
.muted{color:var(--muted)}
.skip{position:absolute;left:-999px}.skip:focus{left:8px;top:8px;background:#fff;padding:8px;z-index:10;border-radius:8px}

/* Header */
.site-header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.header-inner{display:flex;align-items:center;justify-content:space-between;gap:14px;min-height:60px;flex-wrap:wrap}
.logo{display:inline-flex;align-items:center;gap:9px;font-weight:800;font-size:1.15rem;color:var(--ink)}
.logo:hover{text-decoration:none}
.logo-mark{display:inline-grid;place-items:center;width:28px;height:28px;border-radius:7px;background:var(--brand);color:#fff;font-weight:800;font-size:.95rem}
.nav{display:flex;flex-wrap:wrap;gap:4px}
.nav a{color:var(--muted);font-weight:600;font-size:.92rem;padding:7px 10px;border-radius:8px}
.nav a:hover{background:var(--accent);color:var(--brand-d);text-decoration:none}

/* Breadcrumbs */
.crumbs{font-size:.85rem;color:var(--muted);margin:18px 0 6px}
.crumbs .sep{opacity:.5}

/* Hero */
.hero{padding:40px 0 8px}
.hero h1{font-size:2.3rem;margin-bottom:.2em}
.hero p{font-size:1.15rem;color:var(--muted);max-width:640px}

/* Cards / grids */
.grid{display:grid;gap:14px;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));margin:18px 0}
.card{display:block;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:16px 16px 14px;box-shadow:var(--shadow);color:var(--ink);transition:transform .12s ease,box-shadow .12s ease}
.card:hover{text-decoration:none;transform:translateY(-2px);box-shadow:0 6px 22px rgba(16,40,32,.12)}
.card h3{margin:0 0 .25em;font-size:1.05rem;color:var(--brand-d)}
.card p{margin:0;font-size:.9rem;color:var(--muted)}
.cat-label{display:inline-block;font-size:.72rem;font-weight:700;text-transform:uppercase;letter-spacing:.04em;color:var(--brand);background:var(--accent);padding:3px 8px;border-radius:999px;margin-bottom:18px}

/* Section block */
.section{margin:30px 0}
.section h2{margin-top:0}

/* Calculator widget */
.calc{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px;margin:20px 0}
.calc .fields{display:grid;gap:14px;grid-template-columns:repeat(auto-fit,minmax(190px,1fr))}
.field label{display:block;font-weight:600;font-size:.9rem;margin-bottom:5px}
.field .hint{font-weight:400;color:var(--muted);font-size:.8rem}
.field input,.field select{width:100%;padding:11px 12px;font-size:1rem;border:1px solid var(--line);border-radius:10px;background:#fff;color:var(--ink)}
.field input:focus,.field select:focus{outline:2px solid var(--brand);border-color:var(--brand)}
.field.inline{display:flex;gap:10px;align-items:flex-end}
.calc-actions{margin-top:14px;display:flex;gap:10px;flex-wrap:wrap}
.btn{appearance:none;cursor:pointer;border:0;background:var(--brand);color:#fff;font-weight:700;font-size:.95rem;padding:11px 18px;border-radius:10px}
.btn:hover{background:var(--brand-d)}
.btn.ghost{background:var(--accent);color:var(--brand-d)}

/* Calculator output */
.calc-out{margin-top:18px}
.result-head{background:linear-gradient(180deg,var(--accent),#fff);border:1px solid var(--line);border-radius:12px;padding:16px 18px;margin-bottom:14px}
.result-head .big{font-size:2rem;font-weight:800;color:var(--brand-d);line-height:1.1}
.result-head .lbl{font-size:.85rem;color:var(--muted);text-transform:uppercase;letter-spacing:.03em}
table.breakdown{width:100%;border-collapse:collapse;font-size:.95rem}
table.breakdown td{padding:9px 4px;border-bottom:1px solid var(--line)}
table.breakdown td:last-child{text-align:right;font-variant-numeric:tabular-nums;font-weight:600}
table.breakdown tr:last-child td{border-bottom:0}
.note{font-size:.85rem;color:var(--muted);margin-top:10px}
.err{color:#b4451f;font-weight:600}

/* Prose / guide */
.prose{max-width:760px}
.prose h2,.prose h3{color:var(--ink)}
.prose ul,.prose ol{margin:0 0 1em;padding-left:1.3em}
.prose li{margin:.3em 0}
.prose table{width:100%;border-collapse:collapse;margin:1em 0;font-size:.95rem}
.prose th,.prose td{border:1px solid var(--line);padding:8px 10px;text-align:left}
.prose th{background:var(--accent)}

/* FAQ */
.faq details{background:#fff;border:1px solid var(--line);border-radius:10px;padding:2px 16px;margin:10px 0}
.faq summary{cursor:pointer;font-weight:600;padding:12px 0;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";float:right;color:var(--brand);font-weight:800}
.faq details[open] summary::after{content:"\2013"}
.faq details p{padding-bottom:12px;margin:0;color:var(--muted)}

/* Ad slots */
.ad-slot{margin:26px 0;min-height:90px;display:block;text-align:center;overflow:hidden}
.ad-slot small{display:block;font-size:.65rem;color:#aab4af;text-transform:uppercase;letter-spacing:.08em;margin-bottom:4px}

/* Related */
.related{margin:34px 0}
.related h2{font-size:1.2rem}

/* Footer */
.site-footer{background:#fff;border-top:1px solid var(--line);margin-top:50px;padding:34px 0 22px}
.footer-grid{display:grid;gap:24px;grid-template-columns:1.5fr 1fr 1fr}
.footer-grid h4{font-size:.95rem;margin-bottom:.6em}
.footer-grid a{display:block;color:var(--muted);font-size:.9rem;padding:3px 0}
.footer-logo{font-size:1.05rem;margin-bottom:.5em}
.copyright{border-top:1px solid var(--line);margin-top:24px;padding-top:16px}
.copyright p{margin:0;font-size:.82rem}

@media (max-width:680px){
  .hero h1{font-size:1.8rem}.hero p{font-size:1.05rem}
  h1{font-size:1.55rem}
  .footer-grid{grid-template-columns:1fr 1fr}
  .nav{width:100%;overflow-x:auto}
}