/* ============================================================
   CalcNest — shared stylesheet (mobile-first)
   One stylesheet for every page. Vanilla CSS, no dependencies.
   ============================================================ */
:root{
  --brand:#0d7a6f;
  --brand-dark:#095e55;
  --brand-light:#e3f3f1;
  --brand-soft:#f0faf9;
  --ink:#17222e;
  --muted:#5b6b7f;
  --faint:#8a99ab;
  --bg:#f5f7f9;
  --card:#ffffff;
  --border:#e3e9ef;
  --radius:14px;
  --radius-sm:9px;
  --shadow:0 1px 2px rgba(16,24,40,.06),0 6px 16px rgba(16,24,40,.07);
  --font:"Inter",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans",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:1.65;
  font-size:16px;
  -webkit-text-size-adjust:100%;
}
img,svg,canvas{max-width:100%}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
h1,h2,h3{line-height:1.25;letter-spacing:-.01em}
h1{font-size:1.75rem;margin:.4em 0 .5em}
h2{font-size:1.35rem;margin:1.6em 0 .5em}
h3{font-size:1.08rem;margin:1.2em 0 .4em}
p{margin:.7em 0}
.wrap{max-width:1080px;margin:0 auto;padding:0 18px}
.wrap-narrow{max-width:760px;margin:0 auto;padding:0 18px}

/* ---------- Header ---------- */
.site-header{
  position:sticky;top:0;z-index:50;
  background:#fff;border-bottom:1px solid var(--border);
}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:60px}
.logo{display:flex;align-items:center;gap:9px;font-weight:800;font-size:1.25rem;color:var(--ink)}
.logo:hover{text-decoration:none}
.logo-mark{
  width:32px;height:32px;border-radius:9px;flex:none;
  background:linear-gradient(135deg,var(--brand),#12a594);
  display:inline-flex;align-items:center;justify-content:center;
  color:#fff;font-weight:800;font-size:1.05rem;
}
.logo small{font-weight:500;color:var(--muted);font-size:.72rem;display:block;line-height:1}
.nav-toggle{
  border:1px solid var(--border);background:#fff;border-radius:10px;
  width:44px;height:40px;cursor:pointer;display:inline-flex;
  align-items:center;justify-content:center;flex-direction:column;gap:5px;
}
.nav-toggle span{display:block;width:20px;height:2px;background:var(--ink);border-radius:2px}
.nav-drawer{
  display:none;border-top:1px solid var(--border);background:#fff;
  max-height:70vh;overflow:auto;
}
.nav-drawer.open{display:block}
.nav-drawer .wrap{padding-top:10px;padding-bottom:18px}
.nav-drawer h4{margin:12px 0 6px;font-size:.78rem;text-transform:uppercase;letter-spacing:.06em;color:var(--faint)}
.nav-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:2px 14px;list-style:none;margin:0;padding:0}
.nav-grid a{display:block;padding:7px 4px;color:var(--ink);border-radius:8px}
.nav-grid a:hover{background:var(--brand-soft);text-decoration:none}

/* ---------- Hero ---------- */
.hero{
  background:linear-gradient(160deg,#0b3b37 0%,var(--brand-dark) 45%,#0d7a6f 100%);
  color:#fff;padding:52px 0 46px;
}
.hero h1{font-size:2rem;margin:0 0 .35em;color:#fff}
.hero p.lead{font-size:1.06rem;color:#d8ecea;max-width:640px;margin:0}
.hero-search{margin-top:20px;max-width:560px}
.hero-search input{
  width:100%;padding:14px 18px;border:none;border-radius:12px;font-size:1rem;
  box-shadow:var(--shadow);font-family:inherit;
}

/* ---------- Sections & cards ---------- */
.section{padding:34px 0}
.section-title{font-size:1.4rem;margin:0 0 4px}
.section-sub{color:var(--muted);margin:0 0 18px}
.cat-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}
.cat-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:16px 14px;display:block;color:var(--ink);box-shadow:var(--shadow);
}
.cat-card:hover{text-decoration:none;border-color:var(--brand);transform:translateY(-2px);transition:.15s}
.cat-card .emoji{font-size:1.5rem}
.cat-card h3{margin:.35em 0 .15em;font-size:1rem}
.cat-card p{margin:0;color:var(--muted);font-size:.85rem}
.tool-grid{display:grid;grid-template-columns:1fr;gap:12px}
.tool-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:16px;display:flex;gap:12px;align-items:flex-start;color:var(--ink);box-shadow:var(--shadow);
}
.tool-card:hover{text-decoration:none;border-color:var(--brand)}
.tool-card .ticon{
  flex:none;width:42px;height:42px;border-radius:11px;background:var(--brand-light);
  display:flex;align-items:center;justify-content:center;font-size:1.3rem;
}
.tool-card h3{margin:0 0 4px;font-size:1.02rem}
.tool-card p{margin:0;color:var(--muted);font-size:.88rem}

/* ---------- Calculator ---------- */
.breadcrumb{font-size:.85rem;color:var(--faint);margin:18px 0 6px}
.breadcrumb a{color:var(--muted)}
.calc-layout{display:grid;grid-template-columns:1fr;gap:18px;margin-top:14px}
.calc-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  box-shadow:var(--shadow);padding:20px;
}
.calc-card h2{margin-top:0;font-size:1.15rem}
.field{margin:0 0 14px}
.field label{display:block;font-weight:600;font-size:.92rem;margin-bottom:6px}
.field .hint{font-weight:400;color:var(--muted);font-size:.82rem;display:block;margin-top:4px}
.field input[type=number],.field input[type=text],.field input[type=date],
.field select,.field textarea{
  width:100%;padding:11px 13px;border:1.5px solid var(--border);border-radius:var(--radius-sm);
  font-size:1rem;font-family:inherit;color:var(--ink);background:#fff;
}
.field input:focus,.field select:focus,.field textarea:focus{
  outline:none;border-color:var(--brand);box-shadow:0 0 0 3px var(--brand-light);
}
.field-row{display:grid;grid-template-columns:1fr;gap:12px}
.input-group{display:flex;align-items:stretch}
.input-group input{border-radius:var(--radius-sm) 0 0 var(--radius-sm)}
.input-group .unit{
  background:var(--bg);border:1.5px solid var(--border);border-left:none;
  border-radius:0 var(--radius-sm) var(--radius-sm) 0;padding:0 12px;
  display:flex;align-items:center;color:var(--muted);font-size:.9rem;white-space:nowrap;
}
.seg{display:flex;flex-wrap:wrap;gap:8px}
.seg button{
  border:1.5px solid var(--border);background:#fff;border-radius:999px;
  padding:8px 16px;font-size:.92rem;cursor:pointer;font-family:inherit;color:var(--ink);
}
.seg button[aria-pressed=true]{background:var(--brand);border-color:var(--brand);color:#fff;font-weight:600}
.btn{
  display:inline-block;border:none;cursor:pointer;font-family:inherit;
  background:var(--brand);color:#fff;font-weight:700;font-size:1rem;
  padding:13px 26px;border-radius:var(--radius-sm);
}
.btn:hover{background:var(--brand-dark)}
.btn-block{width:100%}
.btn-ghost{background:#fff;color:var(--brand);border:1.5px solid var(--brand)}
.results{
  background:var(--brand-soft);border:1px solid #cde8e4;border-radius:var(--radius);
  padding:18px;margin-top:6px;
}
.results h2{margin-top:0;font-size:1.1rem}
.result-hero{display:flex;flex-wrap:wrap;gap:12px;margin:10px 0 4px}
.result-stat{flex:1 1 140px;background:#fff;border-radius:var(--radius-sm);padding:12px 14px;border:1px solid var(--border)}
.result-stat .k{font-size:.78rem;color:var(--muted);text-transform:uppercase;letter-spacing:.04em}
.result-stat .v{font-size:1.35rem;font-weight:800;color:var(--brand-dark)}
.result-table{width:100%;border-collapse:collapse;margin:12px 0;font-size:.93rem;background:#fff;border-radius:var(--radius-sm);overflow:hidden}
.result-table th,.result-table td{padding:9px 12px;text-align:left;border-bottom:1px solid var(--border)}
.result-table th{background:var(--bg);font-size:.8rem;text-transform:uppercase;letter-spacing:.04em;color:var(--muted)}
.result-table tr:last-child td{border-bottom:none}
.result-table td.num,.result-table th.num{text-align:right;font-variant-numeric:tabular-nums}
.note{
  background:#fff8e6;border:1px solid #f0dfa8;border-radius:var(--radius-sm);
  padding:11px 14px;font-size:.88rem;color:#6b5b1e;margin:14px 0;
}
.note strong{color:#574a16}
.error-msg{color:#b3261e;font-size:.88rem;margin-top:6px;display:none}
.checklist{list-style:none;padding:0;margin:10px 0}
.checklist li{padding:7px 0 7px 30px;position:relative;border-bottom:1px dashed var(--border)}
.checklist li:last-child{border-bottom:none}
.checklist li::before{content:"✓";position:absolute;left:6px;color:var(--brand);font-weight:800}
.checklist li.no::before{content:"✕";color:#b3261e}
.chart-wrap{margin:14px 0;text-align:center}
.chart-wrap svg{max-width:100%;height:auto}
.legend{display:flex;flex-wrap:wrap;gap:14px;justify-content:center;font-size:.85rem;color:var(--muted);margin-top:8px}
.legend i{display:inline-block;width:12px;height:12px;border-radius:3px;margin-right:5px;vertical-align:baseline}

/* ---------- Content / FAQ ---------- */
.prose{max-width:760px}
.prose ul{padding-left:20px}
.faq details{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius-sm);
  margin:10px 0;padding:0;overflow:hidden;
}
.faq summary{
  cursor:pointer;font-weight:600;padding:14px 16px;list-style:none;
  display:flex;justify-content:space-between;align-items:center;gap:10px;
}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";font-size:1.3rem;color:var(--brand);flex:none}
.faq details[open] summary::after{content:"–"}
.faq details .a{padding:0 16px 14px;color:var(--muted)}
.related{display:grid;grid-template-columns:1fr;gap:10px;margin-top:10px}

/* ---------- Footer ---------- */
.site-footer{background:#10222b;color:#c7d5de;margin-top:44px;padding:40px 0 26px;font-size:.92rem}
.footer-grid{display:grid;grid-template-columns:1fr;gap:22px;margin-bottom:24px}
.site-footer h4{color:#fff;font-size:.85rem;text-transform:uppercase;letter-spacing:.06em;margin:0 0 10px}
.site-footer ul{list-style:none;margin:0;padding:0}
.site-footer li{margin:6px 0}
.site-footer a{color:#c7d5de}
.site-footer a:hover{color:#fff}
.footer-brand p{color:#93a7b3;font-size:.88rem;max-width:320px}
.footer-bottom{border-top:1px solid #223a45;padding-top:16px;font-size:.82rem;color:#7d93a0;display:flex;flex-wrap:wrap;gap:8px;justify-content:space-between}

/* ---------- Misc ---------- */
.kbd{background:var(--bg);border:1px solid var(--border);border-radius:5px;padding:1px 7px;font-size:.85em}
.skip-link{position:absolute;left:-9999px}
.skip-link:focus{left:8px;top:8px;background:#fff;padding:8px 12px;z-index:99;border-radius:8px}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}

/* ---------- Breakpoints ---------- */
@media(min-width:640px){
  h1{font-size:2.1rem}
  .hero h1{font-size:2.5rem}
  .cat-grid{grid-template-columns:repeat(3,1fr)}
  .tool-grid{grid-template-columns:repeat(2,1fr)}
  .field-row{grid-template-columns:1fr 1fr}
  .nav-grid{grid-template-columns:repeat(3,1fr)}
  .related{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:2fr 1fr 1fr 1fr}
}
@media(min-width:960px){
  .calc-layout{grid-template-columns:minmax(0,7fr) minmax(0,5fr);align-items:start}
  .cat-grid{grid-template-columns:repeat(4,1fr)}
  .tool-grid{grid-template-columns:repeat(3,1fr)}
  .nav-grid{grid-template-columns:repeat(4,1fr)}
  .results{position:sticky;top:78px}
}