/* KPICalc shared stylesheet — clean B2B tool-site theme */
:root {
  --bg: #ffffff;
  --bg-soft: #f6f8fb;
  --ink: #1a2332;
  --ink-soft: #4a5a73;
  --line: #e3e9f2;
  --brand: #2456e0;
  --brand-dark: #1a41b4;
  --accent: #12b981;
  --warn: #f59e0b;
  --radius: 12px;
  --max: 1080px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Header */
.site-header {
  border-bottom: 1px solid var(--line);
  background: var(--bg);
  position: sticky; top: 0; z-index: 50;
}
.header-inner {
  max-width: var(--max); margin: 0 auto; padding: 14px 20px;
  display: flex; align-items: center; justify-content: space-between;
}
.logo { font-size: 22px; font-weight: 800; color: var(--ink); letter-spacing: -0.5px; }
.logo span { color: var(--brand); }
.logo:hover { text-decoration: none; }
.nav a { margin-left: 22px; color: var(--ink-soft); font-size: 15px; }
.nav a:hover { color: var(--brand); }

/* Layout */
.wrap { max-width: var(--max); margin: 0 auto; padding: 40px 20px 70px; }
.wrap-narrow { max-width: 760px; margin: 0 auto; padding: 40px 20px 70px; }

/* Hero */
.hero { text-align: center; padding: 56px 20px 40px; }
.hero h1 { font-size: 40px; letter-spacing: -1px; margin-bottom: 14px; }
.hero p { color: var(--ink-soft); font-size: 18px; max-width: 640px; margin: 0 auto; }

/* Tool grid */
.tool-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 18px; margin-top: 36px;
}
.tool-card {
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px; background: var(--bg); transition: box-shadow .15s, transform .15s;
  display: block; color: var(--ink);
}
.tool-card:hover { text-decoration: none; box-shadow: 0 8px 24px rgba(36,86,224,.10); transform: translateY(-2px); }
.tool-card h3 { font-size: 18px; margin-bottom: 8px; }
.tool-card p { color: var(--ink-soft); font-size: 14.5px; }
.tool-card .tag {
  display: inline-block; font-size: 12px; font-weight: 700; color: var(--accent);
  background: #e6f9f1; border-radius: 20px; padding: 2px 10px; margin-bottom: 10px;
}
.tool-card.soon { opacity: .62; }
.tool-card.soon .tag { color: var(--warn); background: #fef4e2; }

/* Calculator */
.calc {
  background: var(--bg-soft); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px; margin: 28px 0;
}
.field { margin-bottom: 18px; }
.field label { display: block; font-weight: 600; font-size: 14.5px; margin-bottom: 6px; }
.field .hint { font-weight: 400; color: var(--ink-soft); font-size: 13px; }
.field input {
  width: 100%; padding: 12px 14px; font-size: 16px;
  border: 1px solid var(--line); border-radius: 8px; background: #fff; color: var(--ink);
}
.field input:focus { outline: 2px solid var(--brand); border-color: var(--brand); }
.input-prefix { position: relative; }
.input-prefix span { position: absolute; left: 14px; top: 12px; color: var(--ink-soft); font-size: 16px; }
.input-prefix input { padding-left: 32px; }
.btn {
  display: inline-block; background: var(--brand); color: #fff; border: none;
  font-size: 16px; font-weight: 700; padding: 13px 34px; border-radius: 8px;
  cursor: pointer; width: 100%;
}
.btn:hover { background: var(--brand-dark); }
.results {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px; margin-top: 24px;
}
.result-box {
  background: #fff; border: 1px solid var(--line); border-radius: 10px;
  padding: 16px; text-align: center;
}
.result-box .k { font-size: 13px; color: var(--ink-soft); margin-bottom: 4px; }
.result-box .v { font-size: 26px; font-weight: 800; letter-spacing: -0.5px; }
.result-box .v.pos { color: var(--accent); }
.result-box .v.neg { color: #e5484d; }
.result-note { font-size: 13px; color: var(--ink-soft); margin-top: 14px; }

/* Article */
.article h1 { font-size: 34px; letter-spacing: -0.8px; margin-bottom: 10px; }
.article .lede { color: var(--ink-soft); font-size: 17px; margin-bottom: 8px; }
.article h2 { font-size: 23px; margin: 38px 0 12px; letter-spacing: -0.4px; }
.article p { margin-bottom: 14px; color: #2b3a52; }
.article ul, .article ol { margin: 0 0 16px 22px; color: #2b3a52; }
.article li { margin-bottom: 8px; }
.formula {
  background: var(--bg-soft); border: 1px solid var(--line); border-radius: 8px;
  padding: 16px 20px; font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 15px; margin: 16px 0; overflow-x: auto;
}
.faq { border-top: 1px solid var(--line); margin-top: 10px; }
.faq details { border-bottom: 1px solid var(--line); padding: 14px 0; }
.faq summary { font-weight: 700; cursor: pointer; font-size: 16px; }
.faq summary:hover { color: var(--brand); }
.faq details p { margin: 10px 0 0; color: var(--ink-soft); font-size: 15px; }
.breadcrumb { font-size: 13.5px; color: var(--ink-soft); margin-bottom: 18px; }

/* Ad placeholders (enable after AdSense approval) */
.ad-slot {
  border: 1px dashed var(--line); border-radius: 8px; color: #9aa8c0;
  font-size: 13px; text-align: center; padding: 26px 10px; margin: 30px 0;
  background: #fafbfe;
}

/* Footer */
.site-footer { border-top: 1px solid var(--line); background: var(--bg-soft); }
.footer-inner {
  max-width: var(--max); margin: 0 auto; padding: 34px 20px;
  display: flex; flex-wrap: wrap; gap: 20px; justify-content: space-between;
  font-size: 14px; color: var(--ink-soft);
}
.footer-inner nav a { margin-right: 18px; color: var(--ink-soft); }
.disclaimer {
  max-width: var(--max); margin: 0 auto; padding: 0 20px 30px;
  font-size: 12.5px; color: #9aa8c0;
}

@media (max-width: 640px) {
  .hero h1 { font-size: 30px; }
  .article h1 { font-size: 27px; }
  .calc { padding: 20px; }
  .nav a { margin-left: 14px; }
}