:root {
  --slate-deep: #3A5169;
  --slate-mid: #4E6B85;
  --teal: #2F8F86;
  --teal-dark: #1F6E67;
  --bg: #FAF9F6;
  --surface: #FFFFFF;
  --surface-alt: #F1F0EB;
  --text: #2B3440;
  --text-muted: #6B7686;
  --border: #E2E0D8;
  --radius: 14px;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
}
a { color: var(--teal-dark); }
.container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

header.site-header {
  background: var(--slate-deep);
  color: #fff;
  padding: 16px 0;
}
header.site-header .bar { display: flex; align-items: center; justify-content: space-between; }
header.site-header .brand { font-weight: 700; font-size: 19px; text-decoration: none; color: #fff; }
header.site-header nav a { color: rgba(255,255,255,0.85); text-decoration: none; margin-left: 22px; font-size: 14px; }
header.site-header nav a:hover { color: #fff; }

.hero {
  background: linear-gradient(180deg, rgba(47,143,134,0.08), transparent);
  padding: 44px 0 30px;
}
.hero h1 { font-size: 30px; margin: 0 0 10px; color: var(--slate-deep); }
.hero p { color: var(--text-muted); max-width: 640px; margin: 0 0 0; font-size: 16px; }
.breadcrumb { font-size: 13px; color: var(--text-muted); padding: 16px 0 0; }
.breadcrumb a { color: var(--text-muted); }

.section-title { font-size: 22px; font-weight: 700; margin: 36px 0 16px; color: var(--slate-deep); }

.cat-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 18px; margin-bottom: 30px; }
.cat-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; text-decoration: none; color: var(--text); display: block; }
.cat-card:hover { box-shadow: 0 4px 18px rgba(0,0,0,0.08); }
.cat-card .cat-header { padding: 16px 18px; display: flex; align-items: center; gap: 10px; }
.cat-card .cat-header .icon { font-size: 22px; }
.cat-card .cat-header .title { font-weight: 700; font-size: 15px; color: #fff; flex: 1; }
.cat-card .cat-header .count { color: rgba(255,255,255,0.85); font-size: 12px; }
.cat-card .cat-body { padding: 14px 18px; color: var(--text-muted); font-size: 13px; }

.calc-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 14px; }
.calc-card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 16px; text-decoration: none; color: var(--text); display: flex; gap: 12px; align-items: center; }
.calc-card:hover { border-color: var(--teal); }
.calc-card .icon { font-size: 22px; width: 40px; height: 40px; border-radius: 10px; background: rgba(47,143,134,0.13); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.calc-card .label { font-weight: 600; font-size: 14px; }
.calc-card .desc { font-size: 12px; color: var(--text-muted); margin-top: 2px; }

.calc-page { display: grid; grid-template-columns: minmax(0,1fr) minmax(0,1fr); gap: 26px; margin: 24px 0 50px; }
@media (max-width: 760px) { .calc-page { grid-template-columns: 1fr; } }

.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.card h2 { font-size: 17px; margin: 0 0 16px; }

.form-group { margin-bottom: 16px; }
label { display: block; font-size: 13px; font-weight: 600; color: var(--text-muted); margin-bottom: 6px; }
input[type=text], input[type=number], select {
  width: 100%; padding: 10px 12px; border: 1px solid var(--border); border-radius: 8px;
  font-size: 14px; font-family: inherit; background: var(--surface); color: var(--text);
}
.helper { font-size: 12px; color: var(--text-muted); margin-top: 4px; }

.btn { display: inline-block; background: var(--teal-dark); color: #fff; border: none; border-radius: 8px;
  padding: 12px 22px; font-size: 15px; font-weight: 700; cursor: pointer; text-decoration: none; }
.btn:hover { background: var(--teal); }

.result-card { background: rgba(47,143,134,0.08); border: 1px solid rgba(47,143,134,0.25); border-radius: var(--radius); padding: 22px; }
.result-item { padding: 12px 0; border-bottom: 1px solid rgba(47,143,134,0.18); }
.result-item:last-child { border-bottom: none; }
.result-item .label { font-size: 13px; color: var(--text-muted); }
.result-item .value { font-size: 22px; font-weight: 700; color: var(--teal-dark); }
.result-item.emphasis .value { font-size: 28px; }

.disclaimer { font-size: 12px; color: var(--text-muted); background: var(--surface-alt); border-radius: 10px; padding: 14px 16px; margin-top: 18px; }

footer.site-footer { background: var(--surface-alt); border-top: 1px solid var(--border); margin-top: 60px; padding: 34px 0; }
footer.site-footer .links a { color: var(--text-muted); text-decoration: none; margin-right: 22px; font-size: 13px; font-weight: 600; }
footer.site-footer .fine { font-size: 12px; color: var(--text-muted); margin-top: 16px; }